real life experiment

The Trolley Problem Has Been Tested in 'Real Life' For The Very First Time

It's called the trolley problem, and it's all about how far you'd be willing to go to save lives in an emergency – even if it meant killing somebody.

Now, scientists have tested this famous thought experiment in real life for the first time: with almost 200 human participants, caged mice, electric shocks – and one heck of a decision to make.

You're probably already aware of the classic trolley problem itself, but here's a quick recap - because it's essential to be familiar with it to understand the moral dilemma posed in the new experiments.

Imagine seeing a runaway trolley (or train carriage) hurtling down the tracks, headed directly for five people who are tied to the rails ahead.

The good news is you have the power to save their lives – by simply pulling a lever that will divert the runaway trolley onto another track so that it avoids these poor, tied-up people.

There's just one problem, but it's a big one.

On the other track, there's also a single person tied to the rails, and if you intervene to save the five people on the original track, you'll end up killing this other person.

There are lots of variants and twists that expand upon the dilemma of this classic scenario, each giving a different spin on the hypothetical rightness and wrongness of pulling the metaphorical lever (or not).

But at its heart, the ethical question posed by the trolley problem is whether you should save five lives by taking one – which means getting your hands dirty – or if you should refrain from actively choosing to kill someone, which perversely results in even more death.

This probing dilemma has pondered moral philosophers since the 1960s, but in a provocative twist on the classic problem, psychologists in Belgium have brought the nightmare scenario into the real world (or at least half-way, you might say).

In an experiment with almost 200 student volunteers, participants were admitted to a lab, one at a time, and presented with a difficult choice.

In the lab, an electroshock machine was connected to two separate cages. One of these cages had five mice within it. The other cage had a single mouse occupant. You can probably tell where this is going.

The participants were told they had 20 seconds to make a decision. If they did nothing, a very painful but non-lethal electric shock would be applied to the cage containing the five mice.

If, however, they simply pressed a single button placed before them, then those five mice would be spared the electric shock, which would instead be administered to the single mouse in the other cage.

Before you start penning hate mail, please note: in actual fact, no animals were ever shocked or otherwise harmed in the test.

But during the experiment this was never explained to the participants, who were given the impression their decision would result in electric shocks being applied to at least one mouse, or at most five, depending on how they chose to react.

Ultimately, 84 percent of the participants who took part in the real-life test elected to press the button, sparing the five mice by consciously choosing to zap the other mouse – which, you might reason, results in fewer animals suffering overall ( if they were receiving shocks, which they weren't).

What's interesting is that this real-life experiment didn't match up with another experiment run by the researchers, in which they asked a separate group of participants how they would react in the exact same situation. This time it was purely hypothetical, with no lab setup, mice, or electroshock machine actually present.

In that experiment, only 66 percent of people said they would zap the solitary mouse.

There are a number of limitations with the study, and the extent to which it fully embodies the trolley problem.

For a start, it's hard to ethically equate the prospect of human death with the experience of a mouse receiving an electric shock, and at least some of the participants involved in the experiment later said they saw through the researchers' setup, understanding no animals would be harmed.

But to the extent that it explores the trolley problem, the results suggest that, in the heat of the moment, more of us lean towards consequentialism (based on the overall outcome) than deontological thought (which argues it would be immoral to act to hurt the one mouse, despite the overall outcome), than we might otherwise think.

Hmm. Lots of tricky questions, and no clear answers. What do you think you would do?

The findings are reported in Psychological Science .

First Experimental Proof That Quantum Entanglement Is Real

A Q&A with Caltech alumnus John Clauser on his first experimental proof of quantum entanglement.

When scientists, including Albert Einstein and Erwin Schrödinger, first discovered the phenomenon of entanglement in the 1930s, they were perplexed. Disturbingly, entanglement required two separated particles to remain connected without being in direct contact. In fact, Einstein famously called entanglement “spooky action at a distance,” because the particles seemed to be communicating faster than the speed of light.

Born on December 1, 1942, John Francis Clauser is an American theoretical and experimental physicist known for contributions to the foundations of quantum mechanics, in particular the Clauser–Horne–Shimony–Holt inequality. Clauser was awarded the 2022 Nobel Prize in Physics, jointly with Alain Aspect and Anton Zeilinger “for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science.”

To explain the bizarre implications of entanglement, Einstein, along with Boris Podolsky and Nathan Rosen (EPR), argued that “hidden variables” should be added to quantum mechanics. These could be used to explain entanglement, and to restore “locality” and “causality” to the behavior of the particles. Locality states that objects are only influenced by their immediate surroundings. Causality states that an effect cannot occur before its cause, and that causal signaling cannot propagate faster than light speed. Niels Bohr famously disputed EPR’s argument, while Schrödinger and Wendell Furry, in response to EPR, independently hypothesized that entanglement vanishes with wide-particle separation.

Unfortunately, at the time, no experimental evidence for or against quantum entanglement of widely separated particles was available. Experiments have since proven that entanglement is very real and fundamental to nature. Furthermore, quantum mechanics has now been proven to work, not only at very short distances but also at very great distances. Indeed, China’s quantum-encrypted communications satellite, Micius, (part of the Quantum Experiments at Space Scale (QUESS) research project) relies on quantum entanglement between photons that are separated by thousands of kilometers.

The very first of these experiments was proposed and executed by Caltech alumnus John Clauser (BS ’64) in 1969 and 1972, respectively. His findings are based on Bell’s theorem, devised by CERN theorist John Bell. In 1964, Bell ironically proved that EPR’s argument actually led to the opposite conclusion from what EPR had originally intended to show. Bell demonstrated that quantum entanglement is, in fact, incompatible with EPR’s notion of locality and causality.

In 1969 , while still a graduate student at Columbia University , Clauser, along with Michael Horne, Abner Shimony, and Richard Holt, transformed Bell’s 1964 mathematical theorem into a very specific experimental prediction via what is now called the Clauser–Horne–Shimony–Holt (CHSH) inequality ( Their paper has been cited more than 8,500 times on Google Scholar .) In 1972, when he was a postdoctoral researcher at the University of California Berkeley and Lawrence Berkeley National Laboratory , Clauser and graduate student Stuart Freedman were the first to prove experimentally that two widely separated particles (about 10 feet apart) can be entangled.

Clauser went on to perform three more experiments testing the foundations of quantum mechanics and entanglement, with each new experiment confirming and extending his results. The Freedman–Clauser experiment was the first test of the CHSH inequality. It has now been tested experimentally hundreds of times at laboratories around the world to confirm that quantum entanglement is real.

Clauser’s work earned him the 2010 Wolf Prize in physics. He shared it with Alain Aspect of the Institut d’ Optique and Ecole Polytechnique and Anton Zeilinger of the University of Vienna and the Austrian Academy of Sciences “for an increasingly sophisticated series of tests of Bell’s inequalities, or extensions thereof, using entangled quantum states,” according to the award citation.

Here, John Clauser answers questions about his historical experiments.

We hear that your idea of testing the principles of entanglement was unappealing to other physicists. Can you tell us more about that?

In the 1960s and 70s, experimental testing of quantum mechanics was unpopular at Caltech, Columbia, UC Berkeley, and elsewhere. My faculty at Columbia told me that testing quantum physics was going to destroy my career. While I was performing the 1972 Freedman–Clauser experiment at UC Berkeley, Caltech’s Richard Feynman was highly offended by my impertinent effort and told me that it was tantamount to professing a disbelief in quantum physics. He arrogantly insisted that quantum mechanics is obviously correct and needs no further testing! My reception at UC Berkeley was lukewarm at best and was only possible through the kindness and tolerance of Professors Charlie Townes [PhD ’39, Nobel Laureate ’64] and Howard Shugart [BS ’53], who allowed me to continue my experiments there.

In my correspondence with John Bell , he expressed exactly the opposite sentiment and strongly encouraged me to do an experiment. John Bell’s 1964 seminal work on Bell’s theorem was originally published in the terminal issue of an obscure journal, Physics , and in an underground physics newspaper, Epistemological Letters . It was not until after the 1969 CHSH paper and the 1972 Freedman–Clauser results were published in the Physical Review Letters that John Bell finally openly discussed his work. He was aware of the taboo on questioning quantum mechanics’ foundations and had never discussed it with his CERN co-workers.

What made you want to carry through with the experiments anyway?

Part of the reason that I wanted to test the ideas was because I was still trying to understand them. I found the predictions for entanglement to be sufficiently bizarre that I could not accept them without seeing experimental proof. I also recognized the fundamental importance of the experiments and simply ignored the career advice of my faculty. Moreover, I was having a lot of fun doing some very challenging experimental physics with apparatuses that I built mostly using leftover physics department scrap. Before Stu Freedman and I did the first experiment, I also personally thought that Einstein’s hidden-variable physics might actually be right, and if it is, then I wanted to discover it. I found Einstein’s ideas to be very clear. I found Bohr’s rather muddy and difficult to understand.

What did you expect to find when you did the experiments?

In truth, I really didn’t know what to expect except that I would finally determine who was right—Bohr or Einstein. I admittedly was betting in favor of Einstein but did not actually know who was going to win. It’s like going to the racetrack. You might hope that a certain horse will win, but you don’t really know until the results are in. In this case, it turned out that Einstein was wrong. In the tradition of Caltech’s Richard Feynman and Kip Thorne [BS ’62], who would place scientific bets, I had a bet with quantum physicist Yakir Aharonov on the outcome of the Freedman–Clauser experiment. Curiously, he put up only one dollar to my two. I lost the bet and enclosed a two-dollar bill and congratulations when I mailed him a preprint with our results.

I was very sad to see that my own experiment had proven Einstein wrong. But the experiment gave a 6.3-sigma result against him [a five-sigma result or higher is considered the gold standard for significance in physics]. But then Dick Holt and Frank Pipkin’s competing experiment at Harvard (never published) got the opposite result. I wondered if perhaps I had overlooked some important detail. I went on alone at UC Berkeley to perform three more experimental tests of quantum mechanics. All yielded the same conclusions. Bohr was right, and Einstein was wrong. The Harvard result did not repeat and was faulty. When I reconnected with my Columbia faculty, they all said, “We told you so! Now stop wasting money and go do some real physics.” At that point in my career, the only value in my work was that it demonstrated that I was a reasonably talented experimental physicist. That fact alone got me a job at Lawrence Livermore National Lab doing controlled-fusion plasma physics research.

Can you help us understand exactly what your experiments showed?

In order to clarify what the experiments showed, Mike Horne and I formulated what is now known as Clauser–Horne Local Realism [ 1974 ]. Additional contributions to it were subsequently offered by John Bell and Abner Shimony , so perhaps it is more properly called Bell–Clauser–Horne–Shimony Local Realism . Local Realism was very short-lived as a viable theory. Indeed, it was experimentally refuted even before it was fully formulated. Nonetheless, Local Realism is heuristically important because it shows in detail what quantum mechanics is not .

Local Realism assumes that nature consists of stuff, of objectively real objects, i.e., stuff you can put inside a box. (A box here is an imaginary closed surface defining separated inside and outside volumes.) It further assumes that objects exist whether or not we observe them. Similarly, definite experimental results are assumed to obtain, whether or not we look at them. We may not know what the stuff is, but we assume that it exists and that it is distributed throughout space. Stuff may evolve either deterministically or stochastically. Local Realism assumes that the stuff within a box has intrinsic properties, and that when someone performs an experiment within the box, the probability of any result that obtains is somehow influenced by the properties of the stuff within that box. If one performs say a different experiment with different experimental parameters, then presumably a different result obtains. Now suppose one has two widely separated boxes, each containing stuff. Local Realism further assumes that the experimental parameter choice made in one box cannot affect the experimental outcome in the distant box. Local Realism thereby prohibits spooky action-at-a-distance. It enforces Einstein’s causality that prohibits any such nonlocal cause and effect. Surprisingly, those simple and very reasonable assumptions are sufficient on their own to allow derivation of a second important experimental prediction limiting the correlation between experimental results obtained in the separated boxes. That prediction is the 1974 Clauser–Horne (CH) inequality.

The 1969 CHSH inequality’s derivation had required several minor supplementary assumptions, sometimes called “loopholes.” The CH inequality’s derivation eliminates those supplementary assumptions and is thus more general. Quantum entangled systems exist that disagree with the CH prediction, whereby Local Realism is amenable to experimental disproof. The CHSH and CH inequalities are both violated, not only by the first 1972 Freedman–Clauser experiment and my second 1976 experiment but now by literally hundreds of confirming independent experiments. Various labs have now entangled and violated the CHSH inequality with photon pairs, beryllium ion pairs, ytterbium ion pairs, rubidium atom pairs, whole rubidium-atom cloud pairs, nitrogen vacancies in diamonds, and Josephson phase qubits.

Testing Local Realism and the CH inequality was considered by many researchers to be important to eliminate the CHSH loopholes. Considerable effort was thus marshaled, as quantum optics technology improved and permitted. Testing the CH inequality had become a holy grail challenge for experimentalists. Violation of the CH inequality was finally achieved first in 2013 and again in 2015 at two competing laboratories: Anton Zeilinger’s group at the University of Vienna, and Paul Kwiat’s group at the University of Illinois at Urbana–Champaign. The 2015 experiments involved 56 researchers! Local Realism is now soundly refuted! The agreement between the experiments and quantum mechanics now firmly proves that nonlocal quantum entanglement is real.

What are some of the important technological applications of your work?

One application of my work is to the simplest possible object defined by Local Realism—a single bit of information. Local Realism shows that a single quantum mechanical bit of information, a “qubit,” cannot always be localized in a space-time box. This fact provides the fundamental basis of quantum information theory and quantum cryptography. Caltech’s quantum science and technology program, the 2019 $1.28-billion U.S. National Quantum Initiative, and the 2019 $400 million Israeli National Quantum Initiative all rely on the reality of entanglement. The Chinese Micius quantum-encrypted communications satellite system’s configuration is almost identical to that of the Freedman–Clauser experiment. It uses the CHSH inequality to verify entanglement’s persistence through outer space.

Can you tell us more about your family’s strong connection with Caltech?

My dad, Francis H. Clauser [BS ’34, MS ’35, PhD ’37, Distinguished Alumni Award ’66] and his brother Milton U. Clauser [BS ’34, MS ’35, PhD ’37] were PhD students at Caltech under Theodore von Kármán . Francis Clauser was Clark Blanchard Millikan Professor of Engineering at Caltech (Distinguished Faculty Award ’80) and chair of Caltech’s Division of Engineering and Applied Science. Milton U. Clauser’s son, Milton J. Clauser [PhD ’66], and grandson, Karl Clauser [BS ’86] both went to Caltech. My mom, Catharine McMillan Clauser was Caltech’s humanities librarian, where she met my dad. Her brother, Edwin McMillan [BS ’28, MS ’29], is a Caltech alum and ’51 Nobel Laureate. The family now maintains Caltech’s “Milton and Francis Doctoral Prize” awarded at Caltech commencements.

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The interactions and balances of topological vortex fields cover all short-distance and long-distance contributions, and are the basis of the formation and evolution of cosmic matter. 1.According to the topological vortex field theory, not only light, almost all rays and particles have electric effects. 2.The nature of electricity is perfect fluid.It has no shear stresses,viscosity,or heat conduction.Electric current generates heat because it interacts with vortex current. 3.Entanglement is one of the forms of interaction between vortexes. 4.If you are interested, please see https://zhuanlan.zhihu.com/p/463666584 . Good luck to your team.

The physical characteristics of the fluid vortex center are suitable to be described by energy rather than mass. According to the topological vortex field theory, there are two types of vortex centers: one is constant temperature and the other is variable temperature.

The expansion of space is due to star dynamics or relativity is a part of this.So,entanglement is a natural property present uniformly in universe for quantum particle after adding,saý GR(but not essential beside an arbitrary rational standard taken for measurement in the experiment);hence speed of light has no relation for entanglment of quantum particles at any two points in the same galaxy,or else.These facts have well proven before by many experimentations and are in due course of appĺied field,thus nothing to state about noble prize of current year in physics,but taken as secoded phenomena of the principle of entanglement.Congratulations to the physicists for their good presentations and wise works,granted late.

Fascinating!!!

Quantum Entanglement is perhaps the strangest phenomenon in physics, when some small particles may communicate with each other instantly and over vast distances. How can that happen without violating the maximum speed in the universe, the speed of light?

As this article says, the two ways physicists have used to answer this, that the particles contain hidden variables of unknown natures and that the universe is completely deterministic with all results predefined, have been shown to be incorrect.

Perhaps concepts in String Theory can help. There are 11 possible dimensions in String Theory and I suggest one of them leads a way around, what Einstein called this “spooky action at a distance”. Specifics on this can be found by searching YouTube for “Quantum Entanglement – A String Theory Way”

Bùt credìt of research on particle physics goes for quark-gluon to the America,charm quark to the CERN particĺe physicists.Thus,spin or magnetism required for entanglement has been done in parallel is an established work.

GR in connection to star dynamics is well proven concept taken in all kinds of measurements.

Metaphysics in Quantum Computation field is usual natural part has also been proven and established by experimentation.

All these are distinct works present ofcourse in fractional forms,but commonly adopted jointly in Quantum Computation.

So,alĺ these discoveries with their applications express happiness on behalf of this year’s Physics Nobel Prize with gratefulness to community and all with thanks.

It’s so fascinating contemplating the theme and variations of line of sight communication being moot through the newer mechanical developments

Energy can not be created or destroyed. Our thoughts are forms of energy. And scripture says “as a man think so is he”. Negative thoughts create depression, lack and poverty. Positive thoughts create abundance, wealth and prosperity.

FTL effects and hidden variable are not clearly ruled out and failure of localism could arise from FTL effects, it seems. “Non-local” with “hidden variables” still point to invisible FTL gravity effects, I believe.

Just to clarify, I wanted to note that it still seems “non-localism” and “hidden variables” can fit FTL gravity effects.

Refraction of fire and chief fields to contain high density gravity using quantum Magnetic codings will intensify the field of gravity to project

Quantum energy and its distant entanglement might be a breakthrough for holistic medical science. So therefore mysteries of working of homeopathic remedies on living organisms including humans could be explained and placebo effects of homeopathic remedies can further be explored. Diversity of conventional medical treatment can be boxed into single holistic approach. Thumbs up to marvelous discovery.

I have found a name for what goes on in my mind

ha ha ha… It’s the bizarre world where those embarrassments attempt to qualify as an authority by making word salad… to use their deleterious language once reserved for those sacrifices for the greater good, fire pits, abattoirs, and bomb vests. China still kills them, an economic champion, at what sacrifice? But you may be talking of mirror neurons, that not critical part of physical motion that allows instant … ok. entanglement for such as line dancers, but don’t confuse that with your critical thinking. Remember mirror neurons don’t really care, it’s a temporary allowing of one’s trust to be like another, not forebrain activity.

There is, of course, an information ‘matrix’ associated with the isotropic energy substrate underlying all measurable phenomena. ‘Particles’, therefore, isuue from this substrate and have, ipso facto, access to the information at any point of manifestation. It seems to me. So, no problem really with ‘Spooky Action’.

‘Particles’ isuue from this substrate put this notion well. The interactions and balances of topological vortex fields cover all short-distance and long-distance contributions, wich are the substrate of the formation and evolution of cosmic matter.

There are many here who are eminently more qualified than myself but it seems “apparent” that particles simultaneously exist in a different dimension and in that different dimension are essentially quite local.

you guys are just figuring this whole thing out now, this whole thing had been figured out a long time ago by ancient spiritualism, probably over 10 000 years ago. ancient spirituality had been trying to tell humanity that there is another dimension( “invisible reality”) which is the source of all things happening in this universe and outside the universe, they call it “the all”, some spiritual traditions call it the infinite consciousness, non-duality, the timeless dimension, the formless dimension and more. What’s happening in this universe of relativity is ultimately an illusion because people perceive reality as separate entities and the dimension I’m talking about is beyond forms, time, and space which all the dualistic categories of this universe and mental principles ceases to exist and what left is pure energy, the existence of this present moment(now).thats what science is trying to figure out and spirituality had already figure this whole thing out very long time ago. if someone wants to figure out what’s going on in quantum entanglement, I highly recommend you to access spirituality and non-dual teachings. it is not surprising that science is shocked about this because this whole had been figured out a long time ago, it’s just that science is catching up with spirituality. whatever is happening in the phenomenon of quantum entanglement that seems spooky is governed by that invisible reality called infinite conscioussness, which you cannot understand conceptually but realize as the oness.

Pure drivel, to start with Einstien who this fraudulent author misquotes, said quantum entanglement DOESN’T occur and there was no spooky action at a distance… completely misquoting others and besmirching their names by such slanders is common among such complete frauds as By CALIFORNIA INSTITUTE OF TECHNOLOGY or Not?

Just saying, anyone else ever seen a supposedly academic publication without a long list of authors, and co-authors all wanting credit for the publication as well as a long list of citations? No? Also the long list of word salad comments, anything false spawns false, proof of contraction is abundant, no such thing as quantum entanglement.

i suspect the quantum entanglement experiments are flawed but I have not found the details of these experiments. My skepticism arises from theories surrounding the origin of the universe. Black holes are gravitationally sorted spheres with the densest particles in the center. In order to have a big bang black holes (remnants of adjacent universes would have to collide. The resulting explosion propelled particles into space while preserving some of the more dense particles from the core which formed the early galaxies. The bulk of the mass shot into space the gavitational force decreasing with greater volume and distance from the center dense particles resulting in acceleration. No dark matter required. I am also skeptical of the atomic clock experiment which showed time slows with speed. all the experiment shows is that atomic radius is not constant. As an atom approaches the dense matter from the big bang at the center of the earth its radius deceases. I also suspect the current pole rotation we are in is tied to pre big bang dense matter at the center of the earth, and does not involve liquid iron suddenly changing direction. If quantum entanglement is real the experimental proceedures should be published and available to the layman.

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15 Famous Experiments and Case Studies in Psychology

Chris Drew (PhD)

Dr. Chris Drew is the founder of the Helpful Professor. He holds a PhD in education and has published over 20 articles in scholarly journals. He is the former editor of the Journal of Learning Development in Higher Education. [Image Descriptor: Photo of Chris]

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Psychology has seen thousands upon thousands of research studies over the years. Most of these studies have helped shape our current understanding of human thoughts, behavior, and feelings.

The psychology case studies in this list are considered classic examples of psychological case studies and experiments, which are still being taught in introductory psychology courses up to this day.

Some studies, however, were downright shocking and controversial that you’d probably wonder why such studies were conducted back in the day. Imagine participating in an experiment for a small reward or extra class credit, only to be left scarred for life. These kinds of studies, however, paved the way for a more ethical approach to studying psychology and implementation of research standards such as the use of debriefing in psychology research .

Case Study vs. Experiment

Before we dive into the list of the most famous studies in psychology, let us first review the difference between case studies and experiments.

• It is an in-depth study and analysis of an individual, group, community, or phenomenon. The results of a case study cannot be applied to the whole population, but they can provide insights for further studies.
• It often uses qualitative research methods such as observations, surveys, and interviews.
• It is often conducted in real-life settings rather than in controlled environments.
• An experiment is a type of study done on a sample or group of random participants, the results of which can be generalized to the whole population.
• It often uses quantitative research methods that rely on numbers and statistics.
• It is conducted in controlled environments, wherein some things or situations are manipulated.

See Also: Experimental vs Observational Studies

Famous Experiments in Psychology

1. the marshmallow experiment.

Psychologist Walter Mischel conducted the marshmallow experiment at Stanford University in the 1960s to early 1970s. It was a simple test that aimed to define the connection between delayed gratification and success in life.

The instructions were fairly straightforward: children ages 4-6 were presented a piece of marshmallow on a table and they were told that they would receive a second piece if they could wait for 15 minutes without eating the first marshmallow.

About one-third of the 600 participants succeeded in delaying gratification to receive the second marshmallow. Mischel and his team followed up on these participants in the 1990s, learning that those who had the willpower to wait for a larger reward experienced more success in life in terms of SAT scores and other metrics.

This case study also supported self-control theory , a theory in criminology that holds that people with greater self-control are less likely to end up in trouble with the law!

The classic marshmallow experiment, however, was debunked in a 2018 replication study done by Tyler Watts and colleagues.

This more recent experiment had a larger group of participants (900) and a better representation of the general population when it comes to race and ethnicity. In this study, the researchers found out that the ability to wait for a second marshmallow does not depend on willpower alone but more so on the economic background and social status of the participants.

2. The Bystander Effect

In 1694, Kitty Genovese was murdered in the neighborhood of Kew Gardens, New York. It was told that there were up to 38 witnesses and onlookers in the vicinity of the crime scene, but nobody did anything to stop the murder or call for help.

Such tragedy was the catalyst that inspired social psychologists Bibb Latane and John Darley to formulate the phenomenon called bystander effect or bystander apathy .

Subsequent investigations showed that this story was exaggerated and inaccurate, as there were actually only about a dozen witnesses, at least two of whom called the police. But the case of Kitty Genovese led to various studies that aim to shed light on the bystander phenomenon.

Latane and Darley tested bystander intervention in an experimental study . Participants were asked to answer a questionnaire inside a room, and they would either be alone or with two other participants (who were actually actors or confederates in the study). Smoke would then come out from under the door. The reaction time of participants was tested — how long would it take them to report the smoke to the authorities or the experimenters?

The results showed that participants who were alone in the room reported the smoke faster than participants who were with two passive others. The study suggests that the more onlookers are present in an emergency situation, the less likely someone would step up to help, a social phenomenon now popularly called the bystander effect.

3. Asch Conformity Study

Have you ever made a decision against your better judgment just to fit in with your friends or family? The Asch Conformity Studies will help you understand this kind of situation better.

In this experiment, a group of participants were shown three numbered lines of different lengths and asked to identify the longest of them all. However, only one true participant was present in every group and the rest were actors, most of whom told the wrong answer.

Results showed that the participants went for the wrong answer, even though they knew which line was the longest one in the first place. When the participants were asked why they identified the wrong one, they said that they didn’t want to be branded as strange or peculiar.

This study goes to show that there are situations in life when people prefer fitting in than being right. It also tells that there is power in numbers — a group’s decision can overwhelm a person and make them doubt their judgment.

4. The Bobo Doll Experiment

The Bobo Doll Experiment was conducted by Dr. Albert Bandura, the proponent of social learning theory .

Back in the 1960s, the Nature vs. Nurture debate was a popular topic among psychologists. Bandura contributed to this discussion by proposing that human behavior is mostly influenced by environmental rather than genetic factors.

In the Bobo Doll Experiment, children were divided into three groups: one group was shown a video in which an adult acted aggressively toward the Bobo Doll, the second group was shown a video in which an adult play with the Bobo Doll, and the third group served as the control group where no video was shown.

The children were then led to a room with different kinds of toys, including the Bobo Doll they’ve seen in the video. Results showed that children tend to imitate the adults in the video. Those who were presented the aggressive model acted aggressively toward the Bobo Doll while those who were presented the passive model showed less aggression.

While the Bobo Doll Experiment can no longer be replicated because of ethical concerns, it has laid out the foundations of social learning theory and helped us understand the degree of influence adult behavior has on children.

5. Blue Eye / Brown Eye Experiment

Following the assassination of Martin Luther King Jr. in 1968, third-grade teacher Jane Elliott conducted an experiment in her class. Although not a formal experiment in controlled settings, A Class Divided is a good example of a social experiment to help children understand the concept of racism and discrimination.

The class was divided into two groups: blue-eyed children and brown-eyed children. For one day, Elliott gave preferential treatment to her blue-eyed students, giving them more attention and pampering them with rewards. The next day, it was the brown-eyed students’ turn to receive extra favors and privileges.

As a result, whichever group of students was given preferential treatment performed exceptionally well in class, had higher quiz scores, and recited more frequently; students who were discriminated against felt humiliated, answered poorly in tests, and became uncertain with their answers in class.

This study is now widely taught in sociocultural psychology classes.

6. Stanford Prison Experiment

One of the most controversial and widely-cited studies in psychology is the Stanford Prison Experiment , conducted by Philip Zimbardo at the basement of the Stanford psychology building in 1971. The hypothesis was that abusive behavior in prisons is influenced by the personality traits of the prisoners and prison guards.

The participants in the experiment were college students who were randomly assigned as either a prisoner or a prison guard. The prison guards were then told to run the simulated prison for two weeks. However, the experiment had to be stopped in just 6 days.

The prison guards abused their authority and harassed the prisoners through verbal and physical means. The prisoners, on the other hand, showed submissive behavior. Zimbardo decided to stop the experiment because the prisoners were showing signs of emotional and physical breakdown.

Although the experiment wasn’t completed, the results strongly showed that people can easily get into a social role when others expect them to, especially when it’s highly stereotyped .

7. The Halo Effect

Have you ever wondered why toothpastes and other dental products are endorsed in advertisements by celebrities more often than dentists? The Halo Effect is one of the reasons!

The Halo Effect shows how one favorable attribute of a person can gain them positive perceptions in other attributes. In the case of product advertisements, attractive celebrities are also perceived as intelligent and knowledgeable of a certain subject matter even though they’re not technically experts.

The Halo Effect originated in a classic study done by Edward Thorndike in the early 1900s. He asked military commanding officers to rate their subordinates based on different qualities, such as physical appearance, leadership, dependability, and intelligence.

The results showed that high ratings of a particular quality influences the ratings of other qualities, producing a halo effect of overall high ratings. The opposite also applied, which means that a negative rating in one quality also correlated to negative ratings in other qualities.

Experiments on the Halo Effect came in various formats as well, supporting Thorndike’s original theory. This phenomenon suggests that our perception of other people’s overall personality is hugely influenced by a quality that we focus on.

8. Cognitive Dissonance

There are experiences in our lives when our beliefs and behaviors do not align with each other and we try to justify them in our minds. This is cognitive dissonance , which was studied in an experiment by Leon Festinger and James Carlsmith back in 1959.

In this experiment, participants had to go through a series of boring and repetitive tasks, such as spending an hour turning pegs in a wooden knob. After completing the tasks, they were then paid either $1 or $20 to tell the next participants that the tasks were extremely fun and enjoyable. Afterwards, participants were asked to rate the experiment. Those who were given $1 rated the experiment as more interesting and fun than those who received $20.

The results showed that those who received a smaller incentive to lie experienced cognitive dissonance — $1 wasn’t enough incentive for that one hour of painstakingly boring activity, so the participants had to justify that they had fun anyway.

Famous Case Studies in Psychology

9. little albert.

In 1920, behaviourist theorists John Watson and Rosalie Rayner experimented on a 9-month-old baby to test the effects of classical conditioning in instilling fear in humans.

This was such a controversial study that it gained popularity in psychology textbooks and syllabi because it is a classic example of unethical research studies done in the name of science.

In one of the experiments, Little Albert was presented with a harmless stimulus or object, a white rat, which he wasn’t scared of at first. But every time Little Albert would see the white rat, the researchers would play a scary sound of hammer and steel. After about 6 pairings, Little Albert learned to fear the rat even without the scary sound.

Little Albert developed signs of fear to different objects presented to him through classical conditioning . He even generalized his fear to other stimuli not present in the course of the experiment.

10. Phineas Gage

Phineas Gage is such a celebrity in Psych 101 classes, even though the way he rose to popularity began with a tragic accident. He was a resident of Central Vermont and worked in the construction of a new railway line in the mid-1800s. One day, an explosive went off prematurely, sending a tamping iron straight into his face and through his brain.

Gage survived the accident, fortunately, something that is considered a feat even up to this day. He managed to find a job as a stagecoach after the accident. However, his family and friends reported that his personality changed so much that “he was no longer Gage” (Harlow, 1868).

New evidence on the case of Phineas Gage has since come to light, thanks to modern scientific studies and medical tests. However, there are still plenty of mysteries revolving around his brain damage and subsequent recovery.

11. Anna O.

Anna O., a social worker and feminist of German Jewish descent, was one of the first patients to receive psychoanalytic treatment.

Her real name was Bertha Pappenheim and she inspired much of Sigmund Freud’s works and books on psychoanalytic theory, although they hadn’t met in person. Their connection was through Joseph Breuer, Freud’s mentor when he was still starting his clinical practice.

Anna O. suffered from paralysis, personality changes, hallucinations, and rambling speech, but her doctors could not find the cause. Joseph Breuer was then called to her house for intervention and he performed psychoanalysis, also called the “talking cure”, on her.

Breuer would tell Anna O. to say anything that came to her mind, such as her thoughts, feelings, and childhood experiences. It was noted that her symptoms subsided by talking things out.

However, Breuer later referred Anna O. to the Bellevue Sanatorium, where she recovered and set out to be a renowned writer and advocate of women and children.

12. Patient HM

H.M., or Henry Gustav Molaison, was a severe amnesiac who had been the subject of countless psychological and neurological studies.

Henry was 27 when he underwent brain surgery to cure the epilepsy that he had been experiencing since childhood. In an unfortunate turn of events, he lost his memory because of the surgery and his brain also became unable to store long-term memories.

He was then regarded as someone living solely in the present, forgetting an experience as soon as it happened and only remembering bits and pieces of his past. Over the years, his amnesia and the structure of his brain had helped neuropsychologists learn more about cognitive functions .

Suzanne Corkin, a researcher, writer, and good friend of H.M., recently published a book about his life. Entitled Permanent Present Tense , this book is both a memoir and a case study following the struggles and joys of Henry Gustav Molaison.

13. Chris Sizemore

Chris Sizemore gained celebrity status in the psychology community when she was diagnosed with multiple personality disorder, now known as dissociative identity disorder.

Sizemore has several alter egos, which included Eve Black, Eve White, and Jane. Various papers about her stated that these alter egos were formed as a coping mechanism against the traumatic experiences she underwent in her childhood.

Sizemore said that although she has succeeded in unifying her alter egos into one dominant personality, there were periods in the past experienced by only one of her alter egos. For example, her husband married her Eve White alter ego and not her.

Her story inspired her psychiatrists to write a book about her, entitled The Three Faces of Eve , which was then turned into a 1957 movie of the same title.

14. David Reimer

When David was just 8 months old, he lost his penis because of a botched circumcision operation.

Psychologist John Money then advised Reimer’s parents to raise him as a girl instead, naming him Brenda. His gender reassignment was supported by subsequent surgery and hormonal therapy.

Money described Reimer’s gender reassignment as a success, but problems started to arise as Reimer was growing up. His boyishness was not completely subdued by the hormonal therapy. When he was 14 years old, he learned about the secrets of his past and he underwent gender reassignment to become male again.

Reimer became an advocate for children undergoing the same difficult situation he had been. His life story ended when he was 38 as he took his own life.

15. Kim Peek

Kim Peek was the inspiration behind Rain Man , an Oscar-winning movie about an autistic savant character played by Dustin Hoffman.

The movie was released in 1988, a time when autism wasn’t widely known and acknowledged yet. So it was an eye-opener for many people who watched the film.

In reality, Kim Peek was a non-autistic savant. He was exceptionally intelligent despite the brain abnormalities he was born with. He was like a walking encyclopedia, knowledgeable about travel routes, US zip codes, historical facts, and classical music. He also read and memorized approximately 12,000 books in his lifetime.

This list of experiments and case studies in psychology is just the tip of the iceberg! There are still countless interesting psychology studies that you can explore if you want to learn more about human behavior and dynamics.

You can also conduct your own mini-experiment or participate in a study conducted in your school or neighborhood. Just remember that there are ethical standards to follow so as not to repeat the lasting physical and emotional harm done to Little Albert or the Stanford Prison Experiment participants.

Asch, S. E. (1956). Studies of independence and conformity: I. A minority of one against a unanimous majority. Psychological Monographs: General and Applied, 70 (9), 1–70. https://doi.org/10.1037/h0093718

Bandura, A., Ross, D., & Ross, S. A. (1961). Transmission of aggression through imitation of aggressive models. The Journal of Abnormal and Social Psychology, 63 (3), 575–582. https://doi.org/10.1037/h0045925

Elliott, J., Yale University., WGBH (Television station : Boston, Mass.), & PBS DVD (Firm). (2003). A class divided. New Haven, Conn.: Yale University Films.

Festinger, L., & Carlsmith, J. M. (1959). Cognitive consequences of forced compliance. The Journal of Abnormal and Social Psychology, 58 (2), 203–210. https://doi.org/10.1037/h0041593

Haney, C., Banks, W. C., & Zimbardo, P. G. (1973). A study of prisoners and guards in a simulated prison. Naval Research Review , 30 , 4-17.

Latane, B., & Darley, J. M. (1968). Group inhibition of bystander intervention in emergencies. Journal of Personality and Social Psychology, 10 (3), 215–221. https://doi.org/10.1037/h0026570

Mischel, W. (2014). The Marshmallow Test: Mastering self-control. Little, Brown and Co.

Thorndike, E. (1920) A Constant Error in Psychological Ratings. Journal of Applied Psychology , 4 , 25-29. http://dx.doi.org/10.1037/h0071663

Watson, J. B., & Rayner, R. (1920). Conditioned emotional reactions. Journal of experimental psychology , 3 (1), 1.

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20 Awesome Science Experiments You Can Do Right Now At Home

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We can all agree that science is awesome. And you can bring that awesomeness into your very own home with these 20 safe DIY experiments you can do right now with ordinary household items.

1. Make Objects Seemingly Disappear Refraction is when light changes direction and speed as it passes from one object to another. Only visible objects reflect light. When two materials with similar reflective properties come into contact, light will pass through both materials at the same speed, rendering the other material invisible. Check out this video from BritLab  on how to turn glass invisible using vegetable oil and pyrex glass.

2. Freeze Water Instantly When purified water is cooled to just below freezing point, a quick nudge or an icecube placed in it is all it takes for the water to instantly freeze. You can finally have the power of Frozone from The Incredibles on a very small scale! Check out the video on this "cool" experiment. 

3. Create Oobleck And Make It Dance To The Music Named after a sticky substance in a children’s book by Dr Seuss , Oobleck is a non-Newtonian fluid, which means it can behave as both a solid and a liquid. And when placed on a sound source, the vibrations causes the mixture to gloopily dance. Check out these instructions from Housing A Forest  on how to make this groovy fluid funk out in every way.

4. Create Your Own Hybrid Rocket Engine With a combination of a solid fuel source and a liquid oxidizer, hybrid rocket engines can propel themselves. And on a small scale, you can create your own hybrid rocket engine, using pasta, mouthwash and yeast. Sadly, it won’t propel much, but who said rocket science ain’t easy? Check out this video from NightHawkInLight on how to make this mini engine.

5. Create "Magic Mud" Another non-Newtonian fluid here, this time from the humble potato. "Magic Mud" is actually starch found in potatoes. It’ll remain hard when handled but leave it alone and it turns into a liquid. Make your own “Magic Mud” with this video.

6. Command The Skies And Create A Cloud In A Bottle Not quite a storm in a teacup, but it is a cloud in a bottle. Clouds up in the sky are formed when water vapor cools and condenses into visible water droplets. Create your own cloud in a bottle using a few household items with these wikiHow instructions .

7. Create An Underwater Magical World First synthesized by Adolf van Baeyer in 1871, fluorescein is a non-toxic powder found in highlighter pens, and used by NASA to find shuttles that land in the sea. Create an underwater magical world with this video from NightHawkInLight .

9. Make Your Own Lava Lamp Inside a lava lamp are colored bubbles of wax suspended in a clear or colorless liquid, which changes density when warmed by a heating element at the base, allowing them to rise and fall hypnotically. Create your own lava lamp with these video instructions.

10. Create Magnetic Fluid A ferrofluid is a liquid that contains nanoscale particles of metal, which can become magnetized. And with oil, toner and a magnet , you can create your own ferrofluid and harness the power of magnetism! 

12. Make Waterproof Sand A hydrophobic substance is one that repels water. When sand is combined with a water-resistant chemical, it becomes hydrophobic. So when it comes into contact with water, the sand will remain dry and reusable. Make your own waterproof sand with this video .

13. Make Elephant's Toothpaste Elephant’s toothpaste is a steaming foamy substance created by the rapid decomposition of hydrogen peroxide, which sort of resembles giant-sized toothpaste. Make your own elephant’s toothpaste with these instructions.

14. Make Crystal Bubbles When the temperature falls below 0 o C (32 o F), it’s possible to freeze bubbles into crystals. No instructions needed here, just some bubble mix and chilly weather.

15. Make Moving Liquid Art Mixing dish soap and milk together causes the surface tension of the milk to break down. Throw in different food colorings and create this trippy chemical reaction.

16. Create Colourful Carnations Flowers absorb water through their stems, and if that water has food coloring in it, the flowers will also absorb that color. Create some wonderfully colored flowers with these wikiHow instructions .

17. "Magically" Turn Water Into Wine Turn water into wine with this  video  by experimenter Dave Hax . Because water has a higher density than wine, they can switch places. Amaze your friends with this fun science trick.

18. Release The Energy In Candy (Without Eating It) Dropping a gummy bear into a test tube with potassium chlorate releases the chemical energy inside in an intense chemical reaction. That’s exactly what's happening when you eat candy, kids.

19. Make Water "Mysteriously" Disappear Sodium polyacrylate is a super-absorbent polymer, capable of absorbing up to 300 times its own weight in water. Found in disposable diapers, you can make water disappear in seconds with this video .

20. Create A Rainbow In A Jar Different liquids have different masses and different densities. For example, oil is less dense than water and will float on top of its surface. By combining liquids of different densities and adding food coloring, you can make an entire rainbow in a jar with this video .

There you have it – 20 experiments for you to explore the incredible world of science!

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72 Easy Science Experiments Using Materials You Already Have On Hand

Because science doesn’t have to be complicated.

If there is one thing that is guaranteed to get your students excited, it’s a good science experiment! While some experiments require expensive lab equipment or dangerous chemicals, there are plenty of cool projects you can do with regular household items. We’ve rounded up a big collection of easy science experiments that anybody can try, and kids are going to love them!

Easy Chemistry Science Experiments

Easy physics science experiments, easy biology and environmental science experiments, easy engineering experiments and stem challenges.

1. Taste the Rainbow

Teach your students about diffusion while creating a beautiful and tasty rainbow! Tip: Have extra Skittles on hand so your class can eat a few!

Learn more: Skittles Diffusion

2. Crystallize sweet treats

Crystal science experiments teach kids about supersaturated solutions. This one is easy to do at home, and the results are absolutely delicious!

Learn more: Candy Crystals

3. Make a volcano erupt

This classic experiment demonstrates a chemical reaction between baking soda (sodium bicarbonate) and vinegar (acetic acid), which produces carbon dioxide gas, water, and sodium acetate.

Learn more: Best Volcano Experiments

4. Make elephant toothpaste

This fun project uses yeast and a hydrogen peroxide solution to create overflowing “elephant toothpaste.” Tip: Add an extra fun layer by having kids create toothpaste wrappers for plastic bottles.

5. Blow the biggest bubbles you can

Add a few simple ingredients to dish soap solution to create the largest bubbles you’ve ever seen! Kids learn about surface tension as they engineer these bubble-blowing wands.

Learn more: Giant Soap Bubbles

6. Demonstrate the “magic” leakproof bag

All you need is a zip-top plastic bag, sharp pencils, and water to blow your kids’ minds. Once they’re suitably impressed, teach them how the “trick” works by explaining the chemistry of polymers.

Learn more: Leakproof Bag

7. Use apple slices to learn about oxidation

Have students make predictions about what will happen to apple slices when immersed in different liquids, then put those predictions to the test. Have them record their observations.

Learn more: Apple Oxidation

8. Float a marker man

Their eyes will pop out of their heads when you “levitate” a stick figure right off the table! This experiment works due to the insolubility of dry-erase marker ink in water, combined with the lighter density of the ink.

Learn more: Floating Marker Man

9. Discover density with hot and cold water

There are a lot of easy science experiments you can do with density. This one is extremely simple, involving only hot and cold water and food coloring, but the visuals make it appealing and fun.

Learn more: Layered Water

10. Layer more liquids

This density demo is a little more complicated, but the effects are spectacular. Slowly layer liquids like honey, dish soap, water, and rubbing alcohol in a glass. Kids will be amazed when the liquids float one on top of the other like magic (except it is really science).

Learn more: Layered Liquids

11. Grow a carbon sugar snake

Easy science experiments can still have impressive results! This eye-popping chemical reaction demonstration only requires simple supplies like sugar, baking soda, and sand.

Learn more: Carbon Sugar Snake

12. Mix up some slime

Tell kids you’re going to make slime at home, and watch their eyes light up! There are a variety of ways to make slime, so try a few different recipes to find the one you like best.

13. Make homemade bouncy balls

These homemade bouncy balls are easy to make since all you need is glue, food coloring, borax powder, cornstarch, and warm water. You’ll want to store them inside a container like a plastic egg because they will flatten out over time.

Learn more: Make Your Own Bouncy Balls

14. Create eggshell chalk

Eggshells contain calcium, the same material that makes chalk. Grind them up and mix them with flour, water, and food coloring to make your very own sidewalk chalk.

Learn more: Eggshell Chalk

15. Make naked eggs

This is so cool! Use vinegar to dissolve the calcium carbonate in an eggshell to discover the membrane underneath that holds the egg together. Then, use the “naked” egg for another easy science experiment that demonstrates osmosis .

Learn more: Naked Egg Experiment

16. Turn milk into plastic

This sounds a lot more complicated than it is, but don’t be afraid to give it a try. Use simple kitchen supplies to create plastic polymers from plain old milk. Sculpt them into cool shapes when you’re done!

17. Test pH using cabbage

Teach kids about acids and bases without needing pH test strips! Simply boil some red cabbage and use the resulting water to test various substances—acids turn red and bases turn green.

Learn more: Cabbage pH

18. Clean some old coins

Use common household items to make old oxidized coins clean and shiny again in this simple chemistry experiment. Ask kids to predict (hypothesize) which will work best, then expand the learning by doing some research to explain the results.

Learn more: Cleaning Coins

19. Pull an egg into a bottle

This classic easy science experiment never fails to delight. Use the power of air pressure to suck a hard-boiled egg into a jar, no hands required.

Learn more: Egg in a Bottle

20. Blow up a balloon (without blowing)

Chances are good you probably did easy science experiments like this when you were in school. The baking soda and vinegar balloon experiment demonstrates the reactions between acids and bases when you fill a bottle with vinegar and a balloon with baking soda.

21 Assemble a DIY lava lamp

This 1970s trend is back—as an easy science experiment! This activity combines acid-base reactions with density for a totally groovy result.

22. Explore how sugary drinks affect teeth

The calcium content of eggshells makes them a great stand-in for teeth. Use eggs to explore how soda and juice can stain teeth and wear down the enamel. Expand your learning by trying different toothpaste-and-toothbrush combinations to see how effective they are.

Learn more: Sugar and Teeth Experiment

23. Mummify a hot dog

If your kids are fascinated by the Egyptians, they’ll love learning to mummify a hot dog! No need for canopic jars , just grab some baking soda and get started.

24. Extinguish flames with carbon dioxide

This is a fiery twist on acid-base experiments. Light a candle and talk about what fire needs in order to survive. Then, create an acid-base reaction and “pour” the carbon dioxide to extinguish the flame. The CO2 gas acts like a liquid, suffocating the fire.

25. Send secret messages with invisible ink

Turn your kids into secret agents! Write messages with a paintbrush dipped in lemon juice, then hold the paper over a heat source and watch the invisible become visible as oxidation goes to work.

Learn more: Invisible Ink

26. Create dancing popcorn

This is a fun version of the classic baking soda and vinegar experiment, perfect for the younger crowd. The bubbly mixture causes popcorn to dance around in the water.

27. Shoot a soda geyser sky-high

You’ve always wondered if this really works, so it’s time to find out for yourself! Kids will marvel at the chemical reaction that sends diet soda shooting high in the air when Mentos are added.

Learn more: Soda Explosion

28. Send a teabag flying

Hot air rises, and this experiment can prove it! You’ll want to supervise kids with fire, of course. For more safety, try this one outside.

Learn more: Flying Tea Bags

29. Create magic milk

This fun and easy science experiment demonstrates principles related to surface tension, molecular interactions, and fluid dynamics.

Learn more: Magic Milk Experiment

30. Watch the water rise

Learn about Charles’s Law with this simple experiment. As the candle burns, using up oxygen and heating the air in the glass, the water rises as if by magic.

Learn more: Rising Water

31. Learn about capillary action

Kids will be amazed as they watch the colored water move from glass to glass, and you’ll love the easy and inexpensive setup. Gather some water, paper towels, and food coloring to teach the scientific magic of capillary action.

Learn more: Capillary Action

32. Give a balloon a beard

Equally educational and fun, this experiment will teach kids about static electricity using everyday materials. Kids will undoubtedly get a kick out of creating beards on their balloon person!

Learn more: Static Electricity

33. Find your way with a DIY compass

Here’s an old classic that never fails to impress. Magnetize a needle, float it on the water’s surface, and it will always point north.

Learn more: DIY Compass

34. Crush a can using air pressure

Sure, it’s easy to crush a soda can with your bare hands, but what if you could do it without touching it at all? That’s the power of air pressure!

35. Tell time using the sun

While people use clocks or even phones to tell time today, there was a time when a sundial was the best means to do that. Kids will certainly get a kick out of creating their own sundials using everyday materials like cardboard and pencils.

Learn more: Make Your Own Sundial

36. Launch a balloon rocket

Grab balloons, string, straws, and tape, and launch rockets to learn about the laws of motion.

37. Make sparks with steel wool

All you need is steel wool and a 9-volt battery to perform this science demo that’s bound to make their eyes light up! Kids learn about chain reactions, chemical changes, and more.

Learn more: Steel Wool Electricity

38. Levitate a Ping-Pong ball

Kids will get a kick out of this experiment, which is really all about Bernoulli’s principle. You only need plastic bottles, bendy straws, and Ping-Pong balls to make the science magic happen.

39. Whip up a tornado in a bottle

There are plenty of versions of this classic experiment out there, but we love this one because it sparkles! Kids learn about a vortex and what it takes to create one.

Learn more: Tornado in a Bottle

40. Monitor air pressure with a DIY barometer

This simple but effective DIY science project teaches kids about air pressure and meteorology. They’ll have fun tracking and predicting the weather with their very own barometer.

Learn more: DIY Barometer

41. Peer through an ice magnifying glass

Students will certainly get a thrill out of seeing how an everyday object like a piece of ice can be used as a magnifying glass. Be sure to use purified or distilled water since tap water will have impurities in it that will cause distortion.

Learn more: Ice Magnifying Glass

42. String up some sticky ice

Can you lift an ice cube using just a piece of string? This quick experiment teaches you how. Use a little salt to melt the ice and then refreeze the ice with the string attached.

Learn more: Sticky Ice

43. “Flip” a drawing with water

Light refraction causes some really cool effects, and there are multiple easy science experiments you can do with it. This one uses refraction to “flip” a drawing; you can also try the famous “disappearing penny” trick .

Learn more: Light Refraction With Water

44. Color some flowers

We love how simple this project is to re-create since all you’ll need are some white carnations, food coloring, glasses, and water. The end result is just so beautiful!

45. Use glitter to fight germs

Everyone knows that glitter is just like germs—it gets everywhere and is so hard to get rid of! Use that to your advantage and show kids how soap fights glitter and germs.

Learn more: Glitter Germs

46. Re-create the water cycle in a bag

You can do so many easy science experiments with a simple zip-top bag. Fill one partway with water and set it on a sunny windowsill to see how the water evaporates up and eventually “rains” down.

Learn more: Water Cycle

47. Learn about plant transpiration

Your backyard is a terrific place for easy science experiments. Grab a plastic bag and rubber band to learn how plants get rid of excess water they don’t need, a process known as transpiration.

Learn more: Plant Transpiration

48. Clean up an oil spill

Before conducting this experiment, teach your students about engineers who solve environmental problems like oil spills. Then, have your students use provided materials to clean the oil spill from their oceans.

Learn more: Oil Spill

49. Construct a pair of model lungs

Kids get a better understanding of the respiratory system when they build model lungs using a plastic water bottle and some balloons. You can modify the experiment to demonstrate the effects of smoking too.

Learn more: Model Lungs

50. Experiment with limestone rocks

Kids  love to collect rocks, and there are plenty of easy science experiments you can do with them. In this one, pour vinegar over a rock to see if it bubbles. If it does, you’ve found limestone!

Learn more: Limestone Experiments

51. Turn a bottle into a rain gauge

All you need is a plastic bottle, a ruler, and a permanent marker to make your own rain gauge. Monitor your measurements and see how they stack up against meteorology reports in your area.

Learn more: DIY Rain Gauge

52. Build up towel mountains

This clever demonstration helps kids understand how some landforms are created. Use layers of towels to represent rock layers and boxes for continents. Then pu-u-u-sh and see what happens!

Learn more: Towel Mountains

53. Take a play dough core sample

Learn about the layers of the earth by building them out of Play-Doh, then take a core sample with a straw. ( Love Play-Doh? Get more learning ideas here. )

Learn more: Play Dough Core Sampling

54. Project the stars on your ceiling

Use the video lesson in the link below to learn why stars are only visible at night. Then create a DIY star projector to explore the concept hands-on.

Learn more: DIY Star Projector

55. Make it rain

Use shaving cream and food coloring to simulate clouds and rain. This is an easy science experiment little ones will beg to do over and over.

Learn more: Shaving Cream Rain

56. Blow up your fingerprint

This is such a cool (and easy!) way to look at fingerprint patterns. Inflate a balloon a bit, use some ink to put a fingerprint on it, then blow it up big to see your fingerprint in detail.

57. Snack on a DNA model

Twizzlers, gumdrops, and a few toothpicks are all you need to make this super-fun (and yummy!) DNA model.

Learn more: Edible DNA Model

58. Dissect a flower

Take a nature walk and find a flower or two. Then bring them home and take them apart to discover all the different parts of flowers.

59. Craft smartphone speakers

No Bluetooth speaker? No problem! Put together your own from paper cups and toilet paper tubes.

Learn more: Smartphone Speakers

60. Race a balloon-powered car

Kids will be amazed when they learn they can put together this awesome racer using cardboard and bottle-cap wheels. The balloon-powered “engine” is so much fun too.

Learn more: Balloon-Powered Car

61. Build a Ferris wheel

You’ve probably ridden on a Ferris wheel, but can you build one? Stock up on wood craft sticks and find out! Play around with different designs to see which one works best.

Learn more: Craft Stick Ferris Wheel

62. Design a phone stand

There are lots of ways to craft a DIY phone stand, which makes this a perfect creative-thinking STEM challenge.

63. Conduct an egg drop

Put all their engineering skills to the test with an egg drop! Challenge kids to build a container from stuff they find around the house that will protect an egg from a long fall (this is especially fun to do from upper-story windows).

Learn more: Egg Drop Challenge Ideas

64. Engineer a drinking-straw roller coaster

STEM challenges are always a hit with kids. We love this one, which only requires basic supplies like drinking straws.

Learn more: Straw Roller Coaster

65. Build a solar oven

Explore the power of the sun when you build your own solar ovens and use them to cook some yummy treats. This experiment takes a little more time and effort, but the results are always impressive. The link below has complete instructions.

Learn more: Solar Oven

66. Build a Da Vinci bridge

There are plenty of bridge-building experiments out there, but this one is unique. It’s inspired by Leonardo da Vinci’s 500-year-old self-supporting wooden bridge. Learn how to build it at the link, and expand your learning by exploring more about Da Vinci himself.

Learn more: Da Vinci Bridge

67. Step through an index card

This is one easy science experiment that never fails to astonish. With carefully placed scissor cuts on an index card, you can make a loop large enough to fit a (small) human body through! Kids will be wowed as they learn about surface area.

68. Stand on a pile of paper cups

Combine physics and engineering and challenge kids to create a paper cup structure that can support their weight. This is a cool project for aspiring architects.

Learn more: Paper Cup Stack

69. Test out parachutes

Gather a variety of materials (try tissues, handkerchiefs, plastic bags, etc.) and see which ones make the best parachutes. You can also find out how they’re affected by windy days or find out which ones work in the rain.

Learn more: Parachute Drop

70. Recycle newspapers into an engineering challenge

It’s amazing how a stack of newspapers can spark such creative engineering. Challenge kids to build a tower, support a book, or even build a chair using only newspaper and tape!

Learn more: Newspaper STEM Challenge

71. Use rubber bands to sound out acoustics

Explore the ways that sound waves are affected by what’s around them using a simple rubber band “guitar.” (Kids absolutely love playing with these!)

Learn more: Rubber Band Guitar

72. Assemble a better umbrella

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Three economists win Nobel for their research on how real life events impact society

Scott Horsley

Displayed is a file photo of a Nobel Prize medal on Dec. 8, 2020. The Nobel Prize in economic sciences was awarded to three U.S-based professors for their pioneering work with "natural experiments." Jacquelyn Martin/AP hide caption

Displayed is a file photo of a Nobel Prize medal on Dec. 8, 2020. The Nobel Prize in economic sciences was awarded to three U.S-based professors for their pioneering work with "natural experiments."

Three U.S.-based economists will share this year's Nobel Memorial Prize in Economic Sciences for their innovative work with "natural experiments" – events or policy changes in real life that allow researchers to analyze their impact on society.

David Card of the University of California at Berkeley will receive half the prize, worth 10 million Swedish kronor, or about $1.1 million, the Royal Swedish Academy of Sciences said on Monday . Joshua Angrist of the Masschusetts Institute of Technology and Guido Imbens of Stanford University will share the other half.

The Nobel Prize in literature goes to a Black writer for the first time since 1993

Controlled experiments are common in science and medicine: they allow, for example, to test new drugs by carefully selecting participants and controlling vital aspects to ensure objectivity.

But they are harder in social sciences where it can often be impractical or unethical to conduct randomized trials – unless a real-life event or policy change happens that allow researchers to conduct what are called "natural experiments."

"Natural experiments are everywhere," said Eva Mork, a member of the prize committee. "Thanks to the contributions of the laureates, we researchers are today able to answer key questions for economic and social policy. And thereby the laureates work has greatly benefited society at large."

The Nobel Economics Prize committee members announce the winners of Nobel Memorial Prize in Economic Sciences on Monday. David Card, Joshua Angrist and Guido Imbens were given the award for their research of real-life events and policy changes. Claudio Bresciani/TT News Agency/AFP via Getty Images hide caption

The Nobel Economics Prize committee members announce the winners of Nobel Memorial Prize in Economic Sciences on Monday. David Card, Joshua Angrist and Guido Imbens were given the award for their research of real-life events and policy changes.

The impact of the minimum wage

Card was recognized in part for his groundbreaking work in the early 1990s with the late Princeton economist Alan Krueger, which challenged conventional wisdom about minimum wages.

Economists had long assumed that there was a tradeoff between higher wages and jobs. If the minimum wage went up, it was thought, some workers would get higher pay but others would be laid off.

But when Card and Krueger looked at the actual effect of higher wages on fast food workers , they found no significant drop in employment.

They reached this conclusion by comparing fast food restaurants in New Jersey, which raised its minimum wage, with restaurants in neighboring Pennsylvania, which did not.

A McDonald's sign is shown on July 28 in Houston, Texas. One of the winners of the Nobel Prize in economics on Monday was cited for his work in studying the fast food industry to help determine how minimum wages impact employment. Brandon Bell/Getty Images hide caption

A McDonald's sign is shown on July 28 in Houston, Texas. One of the winners of the Nobel Prize in economics on Monday was cited for his work in studying the fast food industry to help determine how minimum wages impact employment.

Studying cause-and-effect in real life

Meanwhile, Angrist and Imbens were recognized for methodological research that helps tease out cause and effect from these accidental case studies.

During the pandemic, natural experiments have allowed researchers to study the effects of mask mandates, social distancing policies, and supplemental unemployment benefits.

The Nobel Peace Prize goes to journalists in the Philippines and Russia

Imbens said he was "stunned" to get the congratulatory wake-up call at about 2 a.m. in California.

"I was absolutely thrilled to hear the news," Imbens told reporters. "In particular hearing that I got to share this with Josh Angrist and David Card, who are both very good friends of mine."

He noted that Angrist was best man at his wedding.

Imbens said he had no idea how he would spend his share of the prize money.

• minimum wage
• Nobel Prize in Economics
• Joshua Angrist
• Guido Imbens

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February 28, 2020

A real life experiment illuminates the future of books and reading

by Andy Simionato and Karen Ann Donnachie, The Conversation

Books are always transforming. The book we hold today has arrived through a number of materials (clay, papyrus, parchment, paper, pixels) and forms (tablet, scroll, codex, kindle).

The book can be a tool for communication, reading, entertainment, or learning; an object and a status symbol.

The most recent shift, from print media to digital technology , began around the middle of the 20th century. It culminated in two of the most ambitious projects in the history of the book (at least if we believe the corporate hype): the mass-digitization of books by Google and the mass-distribution of electronic books by Amazon .

The survival of bookshops and flourishing of libraries (in real life) defies predictions that the " end of the book " is near. But even the most militant bibliophile will acknowledge how digital technology has called the "idea" of the book into question, once again.

To explore the potential for human-machine collaboration in reading and writing, we built a machine that makes poetry from the pages of any printed book. Ultimately, this project attempts to imagine the future of the book itself.

A machine to read books

Our custom-coded reading-machine reads and interprets real book pages, to create a new " illuminated " book of poetry.

The reading-machine uses Computer Vision and Optical Character Recognition to identify the text on any open book placed under its dual cameras. It then uses Machine Learning and Natural Language Processing technology to "read" the text for meaning, in order to select a short poetic combination of words on the page which it saves by digitally erasing all other words on the page.

Armed with this generated verse, the reading-machine searches the internet for an image—often a doodle or meme, which someone has shared and which has been stored in Google Images—to illustrate the poem.

Once every page in the book has been read, interpreted, and illustrated, the system publishes the results using an online printing service. The resulting volume is then added to a growing archive we call The Library of Nonhuman Books .

From the moment our machine completes its reading until the delivery of the book, our automated-art-system proceeds algorithmically—from interpreting and illuminating the poems, to pagination, cover design and finally adding the endmatter. This is all done without human intervention. The algorithm can generate a seemingly infinite number of readings of any book.

The following poems were produced by the reading-machine from popular texts:

"deep down men try there he's large naked she's even while facing anything."

from E.L. James' " Fifty Shades of Grey "

"how parties popcorn jukebox bathrooms depressed shrug, yeah? all."

from Bret Easton Ellis' " The Rules of Attraction "

"Oh and her bedroom bathroom brushing sending it garter too face hell."

from Truman Capote's Breakfast at Tiffany's"

My algorithm, my muse

So what does all this have to do with the mass-digitization of books?

Faced with growing resistance from authors and publishers concerned with Google's management of copyright, the infoglomerate pivoted away from its primary goal of providing a free corpus of books (a kind of modern day Library of Alexandria ) and towards a more modest index system used for searching inside the books Google had scanned. Google would now serve only short "snippets" of words highlighted on the original page.

Behind the scenes, Google had identified a different use for the texts. Millions of scanned books could be used in a field called Natural Language Processing . NLP allows computers to communicate with people using everyday language rather than code. The books originally scanned for humans were made available to machines for learning, and later imitating, human language.

Algorithmic processes like NLP and Machine Learning hold the promise (or threat) of deferring much of our everyday reading to machines. History has shown that once machines know how to do something, we generally leave them to it . The extent to which we do this will depend on how much we value reading.

If we continue to defer our reading (and writing) to machines, we might make literature with our artificially intelligent counterparts. What will poetry become, with an algorithm as our muse?

We already have clues to this: from the almost obligatory use of emojis or Japanese Kaomoji (顔文字) as visual shorthand for the emotional intent of our digital communication, to the layered meanings of internet memes, to the auto-generation of " fake news " stories. These are the image-word hybrids we find in post-literate social media.

To hide a leaf

Take the book, my friend, and read your eyes out, you will never find there what I find.

Ralph Waldo Emerson's Spiritual Laws

Emerson's challenge highlights the subjectivity we bring to reading. When we started working on the reading-machine we focused on discovering patterns of words within larger bodies of texts that have always been there, but have remained "hidden in plain sight." Every attempt by the reading-machine generated new poems, all of them made from words that remained in their original positions on the pages of books.

The notion of a single book consisting of infinite readings is not new. We originally conceived our reading-machine as a way of making a mythical Book of Sand , described by Jorge Luis Borges in his 1975 parable.

Borges' story is about the narrator's encounter with an endless book which continuously recombines its words and images. Many have compared this impossible book to the internet of today. Our reading-machine, with the turn of each page of any physical book, calculates combinations of words on that page which, until that moment, have been seen, but not consciously perceived by the reader.

The title of our early version of the work was To Hide a Leaf. It was generated by chance when a prototype of the reading-machine was presented with a page from a book of Borges' stories. The complete sentence from which the words were taken is:

"Somewhere I recalled reading that the best place to hide a leaf is in a forest."

The latent verse our machine attempts to reveal in books also hides in plain sight, like a leaf in a forest; and the idea is also a play on a page being generally referred to as a "leaf of a book."

Like the Book of Sand, perhaps all books can be seen as combinatorial machines . We believed we could write an algorithm that could unlock new meanings in existing books , using only the text within that book as the key.

Philosopher Boris Groys described the result of the mass-digitization of the book as Words Without Grammar , suggesting clouds of disconnected words.

Our reading-machine, and the Library of Nonhuman Books it is generating, is an attempt to imagine the book to come after these clouds of "words without grammar." We have found the results are sometimes comical, often nonsensical, occasionally infuriating and, every now and then, even poetic.

Provided by The Conversation

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Science Literacy, Education, Communication

8 Fun Science Experiments You Can Easily Do at Home

Looking for a science project to do with kids? These experiments go beyond the trivial and incorporate real-world scientific research.

SciStarter Blog

Around the world, millions of kids are headed back to school in a totally different way. Classes are online. Teachers talk to students in virtual classrooms. And parents are often left looking for new, hands-on science learning opportunities.

We’ve got your back. Here are eight fun and easy science experiments that you can do at home with kids of all ages. What’s more, each of these science projects ties into real-life research efforts through citizen science, where volunteers help experts collect and analyze data.

RELATED: VIRTUAL DISSECTION: ANIMALEARNING FROM HOME

Make Wild Sourdough

It seems like the whole world is baking homemade sourdough bread right now. Sourdough took on broad appeal when the baker’s yeast disappeared from store shelves. Unlike other baking projects, sourdough doesn’t need store bought yeast. Instead, it’s made with sourdough starter.

RELATED: FREE SCIENCE EDUCATION E-BOOKS

If you have flour, you can easily experiment with making your own sourdough starter.  Wild sourdough starters  tap into the abundant yeast in our homes and puts them to work making delicious bread. When it comes to science experiments you can do at home, few could be more delicious and rewarding than this one. You’ll also be helping scientists out along the way.

RELATED: BACK TO SCHOOL WITH CITIZEN SCIENCE

The Wild Sourdough Project is a global science experiment that hopes to discover how sourdough starter communities form over time. The team behind the effort is hoping to unravel how factors like geography and different kinds of flour affect the yeast communities. Best of all, the effort has a step-by-step guide that lets you learn how to make your own sourdough starter.

Take Part: Make Your Own Sourdough for Science

Create a Cloud in a Jar

Clouds are an important and often overlooked driver of Earth’s temperature. They trap sunlight in, but they also reflect it back into space. That role has climate scientists rushing to study our planet’s clouds, and how they’re changing.  NASA’s GLOBE Observer: Clouds  project taps citizen scientists to provide pictures of the sky, plus observations of cloud cover, type, sky conditions and visibility. That data helps info real science research and verify what satellites are seeing from space.

You can get involved with your kids and enrich the experience by adding lessons about clouds. For example, NASA has added a number of fun and easy ways to learn about climate science and clouds, including science experiments. One of the best related projects is to make a cloud in a jar. This simple science experiment is a powerful way to demonstrate how clouds work. You only need water, ice, a jar, and a few minutes of time.

Take Part: Join NASA’s Globe Observer Clouds

Measure Rain and Snow with CoCoRaHS

Fall is approaching fast, which means many of us will soon be at home watching rain and snow out the window. Instead of succumbing to the gloom, why not make that weather into a fun science experiment for your kids?

The CoCoRaHS weather monitoring program, or Community Collaborative Rain, Hail, and Snow Network, is a network of volunteers who measure and report on precipitation. CoCoRaHS emphasizes training and education, and they even have an interactive website rich in educational resources and even National Weather Service lesson plans you can use at home.

RELATED: Getting Creative with Remote Science Learning

As a volunteer, you’ll use the same low-cost weather gauges that meteorologists and cities use. Then, when it rains, snows or hails, you’ll submit your precipitation data to the website where you can compare it to others in real-time. That information also helps out the National Weather Service, as well as researchers, farmers, emergency managers — and curious people everywhere.

Take Part: Join the CoCoRaHS Weather Monitoring Network

Plant a Pollinator Garden

Pollinators play a vital role in Earth’s ecosystems, and yet they’re threatened by pesticides, disease, habitat loss and even climate change. That has many people searching for  ways to help save bees and other pollinators .

There are many options to chip in, but one of the most impactful things you and your kids can do at home is  plant a pollinator garden .

Not only will this serve to help struggling pollinators, it can also serve as a long-term science laboratory at home. SciStarter, the citizen-science group behind this blog post, has compiled an entire group of at-home science projects that can be done from your pollinator garden. You can watch moths, butterflies, bees, hummingbirds and more, then help scientists track their migration across the country.

Take Part: Plant a Pollinator Garden

Build a Bee Condo

If you already have a bumper garden at home, or it’s getting too cold to think about planting just yet, you can still stay indoors and help pollinators. The group behind National Pollinator Week has put together instructions for how you can build a home for native bees, called a bee condo. Unlike domesticated honey bees that live in apiaries, most native, wild bees you find in your backyard actually burrow their homes into the soil or a tree.

By building a bee condo, you can encourage bees to live nearby and also get a fun, DIY science experiment to do at home. Once it’s up, you can watch what kinds of critters take up residence there and report back on the results for science.

Take Part: Build a Bee Condo

Scan the Night Sky

Around the world, light pollution from buildings and street lamps is blocking our view of the night sky. Most people who live in cities have never seen a truly dark sky, or the Milky Way. That’s not just bad for humans, it’s also bad for the plants, animals and insects who are disrupted by light pollution.

If you have a budding astronomy-lover in the house, you can participate in a science project called  Globe at Night  that aims to create a world-wide measure of light pollution in our night sky.

For this science experiment, you can start making observations using only a smartphone. You’ll mark the sky’s darkness by how many stars you can see. And you can get a sky quality meter through the project to help record even better data.

Take Part: Measure Light Pollution in Your Community

Measure Water Quality

More than 1.5 million volunteers from across the planet are already taking part in a science experiment to track — and protect — Earth’s waterways. The citizen science effort is called the  EarthEcho Water Challenge , and it has users buy a water test kit for about $25, then start collecting basic water data.

Volunteers record things like water clarity, temperature, pH and dissolved oxygen. That data gets plugged into a large database, where it’s used for real science research and to help protect waterways.

Take Part: Join the Earth Echo Water Challenge

Study the Vitamin C in Your Juice

Back in the golden age of sailing, sailors worried that they’d get scurvy. A lack of vitamin C during long voyages can cause a host of health problems. Scurvy leaves you weak, causes skin problems and gum disease, and makes it harder to heal. Scurvy can even kill you. This isn’t just an old-timey concern, either. Future space explorers will have to worry about vitamin C as they head off to explore the solar system. And that’s the angle utilized by a fun citizen science project called  Space Scurvy .

The project asks students to use household items to test the vitamin C content of juices from their schools and homes. The necessary tools for this science experiment should be easy to come by, and the site has fun and simple directions for you to follow.

Take Part: Measure Vitamin C for the Space Scurvy Project

Note: Some of these projects are SciStarter Affiliates. You can use your SciStarter account email to join and earn credit for your participation in your SciStarter dashboard.

Citizen Science Lessons During the Pandemic

About the Author

Eric Betz is a science and tech writer for Discover Magazine, Astronomy Magazine, and others. He is a lover of #darkskies and pale blue dots.

19+ Experimental Design Examples (Methods + Types)

Ever wondered how scientists discover new medicines, psychologists learn about behavior, or even how marketers figure out what kind of ads you like? Well, they all have something in common: they use a special plan or recipe called an "experimental design."

Imagine you're baking cookies. You can't just throw random amounts of flour, sugar, and chocolate chips into a bowl and hope for the best. You follow a recipe, right? Scientists and researchers do something similar. They follow a "recipe" called an experimental design to make sure their experiments are set up in a way that the answers they find are meaningful and reliable.

Experimental design is the roadmap researchers use to answer questions. It's a set of rules and steps that researchers follow to collect information, or "data," in a way that is fair, accurate, and makes sense.

Long ago, people didn't have detailed game plans for experiments. They often just tried things out and saw what happened. But over time, people got smarter about this. They started creating structured plans—what we now call experimental designs—to get clearer, more trustworthy answers to their questions.

In this article, we'll take you on a journey through the world of experimental designs. We'll talk about the different types, or "flavors," of experimental designs, where they're used, and even give you a peek into how they came to be.

What Is Experimental Design?

Alright, before we dive into the different types of experimental designs, let's get crystal clear on what experimental design actually is.

Imagine you're a detective trying to solve a mystery. You need clues, right? Well, in the world of research, experimental design is like the roadmap that helps you find those clues. It's like the game plan in sports or the blueprint when you're building a house. Just like you wouldn't start building without a good blueprint, researchers won't start their studies without a strong experimental design.

So, why do we need experimental design? Think about baking a cake. If you toss ingredients into a bowl without measuring, you'll end up with a mess instead of a tasty dessert.

Similarly, in research, if you don't have a solid plan, you might get confusing or incorrect results. A good experimental design helps you ask the right questions ( think critically ), decide what to measure ( come up with an idea ), and figure out how to measure it (test it). It also helps you consider things that might mess up your results, like outside influences you hadn't thought of.

For example, let's say you want to find out if listening to music helps people focus better. Your experimental design would help you decide things like: Who are you going to test? What kind of music will you use? How will you measure focus? And, importantly, how will you make sure that it's really the music affecting focus and not something else, like the time of day or whether someone had a good breakfast?

In short, experimental design is the master plan that guides researchers through the process of collecting data, so they can answer questions in the most reliable way possible. It's like the GPS for the journey of discovery!

History of Experimental Design

Around 350 BCE, people like Aristotle were trying to figure out how the world works, but they mostly just thought really hard about things. They didn't test their ideas much. So while they were super smart, their methods weren't always the best for finding out the truth.

Fast forward to the Renaissance (14th to 17th centuries), a time of big changes and lots of curiosity. People like Galileo started to experiment by actually doing tests, like rolling balls down inclined planes to study motion. Galileo's work was cool because he combined thinking with doing. He'd have an idea, test it, look at the results, and then think some more. This approach was a lot more reliable than just sitting around and thinking.

Now, let's zoom ahead to the 18th and 19th centuries. This is when people like Francis Galton, an English polymath, started to get really systematic about experimentation. Galton was obsessed with measuring things. Seriously, he even tried to measure how good-looking people were ! His work helped create the foundations for a more organized approach to experiments.

Next stop: the early 20th century. Enter Ronald A. Fisher , a brilliant British statistician. Fisher was a game-changer. He came up with ideas that are like the bread and butter of modern experimental design.

Fisher invented the concept of the " control group "—that's a group of people or things that don't get the treatment you're testing, so you can compare them to those who do. He also stressed the importance of " randomization ," which means assigning people or things to different groups by chance, like drawing names out of a hat. This makes sure the experiment is fair and the results are trustworthy.

Around the same time, American psychologists like John B. Watson and B.F. Skinner were developing " behaviorism ." They focused on studying things that they could directly observe and measure, like actions and reactions.

Skinner even built boxes—called Skinner Boxes —to test how animals like pigeons and rats learn. Their work helped shape how psychologists design experiments today. Watson performed a very controversial experiment called The Little Albert experiment that helped describe behaviour through conditioning—in other words, how people learn to behave the way they do.

In the later part of the 20th century and into our time, computers have totally shaken things up. Researchers now use super powerful software to help design their experiments and crunch the numbers.

With computers, they can simulate complex experiments before they even start, which helps them predict what might happen. This is especially helpful in fields like medicine, where getting things right can be a matter of life and death.

Also, did you know that experimental designs aren't just for scientists in labs? They're used by people in all sorts of jobs, like marketing, education, and even video game design! Yes, someone probably ran an experiment to figure out what makes a game super fun to play.

So there you have it—a quick tour through the history of experimental design, from Aristotle's deep thoughts to Fisher's groundbreaking ideas, and all the way to today's computer-powered research. These designs are the recipes that help people from all walks of life find answers to their big questions.

Key Terms in Experimental Design

Before we dig into the different types of experimental designs, let's get comfy with some key terms. Understanding these terms will make it easier for us to explore the various types of experimental designs that researchers use to answer their big questions.

Independent Variable : This is what you change or control in your experiment to see what effect it has. Think of it as the "cause" in a cause-and-effect relationship. For example, if you're studying whether different types of music help people focus, the kind of music is the independent variable.

Dependent Variable : This is what you're measuring to see the effect of your independent variable. In our music and focus experiment, how well people focus is the dependent variable—it's what "depends" on the kind of music played.

Control Group : This is a group of people who don't get the special treatment or change you're testing. They help you see what happens when the independent variable is not applied. If you're testing whether a new medicine works, the control group would take a fake pill, called a placebo , instead of the real medicine.

Experimental Group : This is the group that gets the special treatment or change you're interested in. Going back to our medicine example, this group would get the actual medicine to see if it has any effect.

Randomization : This is like shaking things up in a fair way. You randomly put people into the control or experimental group so that each group is a good mix of different kinds of people. This helps make the results more reliable.

Sample : This is the group of people you're studying. They're a "sample" of a larger group that you're interested in. For instance, if you want to know how teenagers feel about a new video game, you might study a sample of 100 teenagers.

Bias : This is anything that might tilt your experiment one way or another without you realizing it. Like if you're testing a new kind of dog food and you only test it on poodles, that could create a bias because maybe poodles just really like that food and other breeds don't.

Data : This is the information you collect during the experiment. It's like the treasure you find on your journey of discovery!

Replication : This means doing the experiment more than once to make sure your findings hold up. It's like double-checking your answers on a test.

Hypothesis : This is your educated guess about what will happen in the experiment. It's like predicting the end of a movie based on the first half.

Steps of Experimental Design

Alright, let's say you're all fired up and ready to run your own experiment. Cool! But where do you start? Well, designing an experiment is a bit like planning a road trip. There are some key steps you've got to take to make sure you reach your destination. Let's break it down:

• Ask a Question : Before you hit the road, you've got to know where you're going. Same with experiments. You start with a question you want to answer, like "Does eating breakfast really make you do better in school?"
• Do Some Homework : Before you pack your bags, you look up the best places to visit, right? In science, this means reading up on what other people have already discovered about your topic.
• Form a Hypothesis : This is your educated guess about what you think will happen. It's like saying, "I bet this route will get us there faster."
• Plan the Details : Now you decide what kind of car you're driving (your experimental design), who's coming with you (your sample), and what snacks to bring (your variables).
• Randomization : Remember, this is like shuffling a deck of cards. You want to mix up who goes into your control and experimental groups to make sure it's a fair test.
• Run the Experiment : Finally, the rubber hits the road! You carry out your plan, making sure to collect your data carefully.
• Analyze the Data : Once the trip's over, you look at your photos and decide which ones are keepers. In science, this means looking at your data to see what it tells you.
• Draw Conclusions : Based on your data, did you find an answer to your question? This is like saying, "Yep, that route was faster," or "Nope, we hit a ton of traffic."
• Share Your Findings : After a great trip, you want to tell everyone about it, right? Scientists do the same by publishing their results so others can learn from them.
• Do It Again? : Sometimes one road trip just isn't enough. In the same way, scientists often repeat their experiments to make sure their findings are solid.

So there you have it! Those are the basic steps you need to follow when you're designing an experiment. Each step helps make sure that you're setting up a fair and reliable way to find answers to your big questions.

Let's get into examples of experimental designs.

1) True Experimental Design

In the world of experiments, the True Experimental Design is like the superstar quarterback everyone talks about. Born out of the early 20th-century work of statisticians like Ronald A. Fisher, this design is all about control, precision, and reliability.

Researchers carefully pick an independent variable to manipulate (remember, that's the thing they're changing on purpose) and measure the dependent variable (the effect they're studying). Then comes the magic trick—randomization. By randomly putting participants into either the control or experimental group, scientists make sure their experiment is as fair as possible.

No sneaky biases here!

True Experimental Design Pros

The pros of True Experimental Design are like the perks of a VIP ticket at a concert: you get the best and most trustworthy results. Because everything is controlled and randomized, you can feel pretty confident that the results aren't just a fluke.

True Experimental Design Cons

However, there's a catch. Sometimes, it's really tough to set up these experiments in a real-world situation. Imagine trying to control every single detail of your day, from the food you eat to the air you breathe. Not so easy, right?

True Experimental Design Uses

The fields that get the most out of True Experimental Designs are those that need super reliable results, like medical research.

When scientists were developing COVID-19 vaccines, they used this design to run clinical trials. They had control groups that received a placebo (a harmless substance with no effect) and experimental groups that got the actual vaccine. Then they measured how many people in each group got sick. By comparing the two, they could say, "Yep, this vaccine works!"

So next time you read about a groundbreaking discovery in medicine or technology, chances are a True Experimental Design was the VIP behind the scenes, making sure everything was on point. It's been the go-to for rigorous scientific inquiry for nearly a century, and it's not stepping off the stage anytime soon.

2) Quasi-Experimental Design

So, let's talk about the Quasi-Experimental Design. Think of this one as the cool cousin of True Experimental Design. It wants to be just like its famous relative, but it's a bit more laid-back and flexible. You'll find quasi-experimental designs when it's tricky to set up a full-blown True Experimental Design with all the bells and whistles.

Quasi-experiments still play with an independent variable, just like their stricter cousins. The big difference? They don't use randomization. It's like wanting to divide a bag of jelly beans equally between your friends, but you can't quite do it perfectly.

In real life, it's often not possible or ethical to randomly assign people to different groups, especially when dealing with sensitive topics like education or social issues. And that's where quasi-experiments come in.

Quasi-Experimental Design Pros

Even though they lack full randomization, quasi-experimental designs are like the Swiss Army knives of research: versatile and practical. They're especially popular in fields like education, sociology, and public policy.

For instance, when researchers wanted to figure out if the Head Start program , aimed at giving young kids a "head start" in school, was effective, they used a quasi-experimental design. They couldn't randomly assign kids to go or not go to preschool, but they could compare kids who did with kids who didn't.

Quasi-Experimental Design Cons

Of course, quasi-experiments come with their own bag of pros and cons. On the plus side, they're easier to set up and often cheaper than true experiments. But the flip side is that they're not as rock-solid in their conclusions. Because the groups aren't randomly assigned, there's always that little voice saying, "Hey, are we missing something here?"

Quasi-Experimental Design Uses

Quasi-Experimental Design gained traction in the mid-20th century. Researchers were grappling with real-world problems that didn't fit neatly into a laboratory setting. Plus, as society became more aware of ethical considerations, the need for flexible designs increased. So, the quasi-experimental approach was like a breath of fresh air for scientists wanting to study complex issues without a laundry list of restrictions.

In short, if True Experimental Design is the superstar quarterback, Quasi-Experimental Design is the versatile player who can adapt and still make significant contributions to the game.

3) Pre-Experimental Design

Now, let's talk about the Pre-Experimental Design. Imagine it as the beginner's skateboard you get before you try out for all the cool tricks. It has wheels, it rolls, but it's not built for the professional skatepark.

Similarly, pre-experimental designs give researchers a starting point. They let you dip your toes in the water of scientific research without diving in head-first.

So, what's the deal with pre-experimental designs?

Pre-Experimental Designs are the basic, no-frills versions of experiments. Researchers still mess around with an independent variable and measure a dependent variable, but they skip over the whole randomization thing and often don't even have a control group.

It's like baking a cake but forgetting the frosting and sprinkles; you'll get some results, but they might not be as complete or reliable as you'd like.

Pre-Experimental Design Pros

Why use such a simple setup? Because sometimes, you just need to get the ball rolling. Pre-experimental designs are great for quick-and-dirty research when you're short on time or resources. They give you a rough idea of what's happening, which you can use to plan more detailed studies later.

A good example of this is early studies on the effects of screen time on kids. Researchers couldn't control every aspect of a child's life, but they could easily ask parents to track how much time their kids spent in front of screens and then look for trends in behavior or school performance.

Pre-Experimental Design Cons

But here's the catch: pre-experimental designs are like that first draft of an essay. It helps you get your ideas down, but you wouldn't want to turn it in for a grade. Because these designs lack the rigorous structure of true or quasi-experimental setups, they can't give you rock-solid conclusions. They're more like clues or signposts pointing you in a certain direction.

Pre-Experimental Design Uses

This type of design became popular in the early stages of various scientific fields. Researchers used them to scratch the surface of a topic, generate some initial data, and then decide if it's worth exploring further. In other words, pre-experimental designs were the stepping stones that led to more complex, thorough investigations.

So, while Pre-Experimental Design may not be the star player on the team, it's like the practice squad that helps everyone get better. It's the starting point that can lead to bigger and better things.

4) Factorial Design

Now, buckle up, because we're moving into the world of Factorial Design, the multi-tasker of the experimental universe.

Imagine juggling not just one, but multiple balls in the air—that's what researchers do in a factorial design.

In Factorial Design, researchers are not satisfied with just studying one independent variable. Nope, they want to study two or more at the same time to see how they interact.

It's like cooking with several spices to see how they blend together to create unique flavors.

Factorial Design became the talk of the town with the rise of computers. Why? Because this design produces a lot of data, and computers are the number crunchers that help make sense of it all. So, thanks to our silicon friends, researchers can study complicated questions like, "How do diet AND exercise together affect weight loss?" instead of looking at just one of those factors.

Factorial Design Pros

This design's main selling point is its ability to explore interactions between variables. For instance, maybe a new study drug works really well for young people but not so great for older adults. A factorial design could reveal that age is a crucial factor, something you might miss if you only studied the drug's effectiveness in general. It's like being a detective who looks for clues not just in one room but throughout the entire house.

Factorial Design Cons

However, factorial designs have their own bag of challenges. First off, they can be pretty complicated to set up and run. Imagine coordinating a four-way intersection with lots of cars coming from all directions—you've got to make sure everything runs smoothly, or you'll end up with a traffic jam. Similarly, researchers need to carefully plan how they'll measure and analyze all the different variables.

Factorial Design Uses

Factorial designs are widely used in psychology to untangle the web of factors that influence human behavior. They're also popular in fields like marketing, where companies want to understand how different aspects like price, packaging, and advertising influence a product's success.

And speaking of success, the factorial design has been a hit since statisticians like Ronald A. Fisher (yep, him again!) expanded on it in the early-to-mid 20th century. It offered a more nuanced way of understanding the world, proving that sometimes, to get the full picture, you've got to juggle more than one ball at a time.

So, if True Experimental Design is the quarterback and Quasi-Experimental Design is the versatile player, Factorial Design is the strategist who sees the entire game board and makes moves accordingly.

5) Longitudinal Design

Alright, let's take a step into the world of Longitudinal Design. Picture it as the grand storyteller, the kind who doesn't just tell you about a single event but spins an epic tale that stretches over years or even decades. This design isn't about quick snapshots; it's about capturing the whole movie of someone's life or a long-running process.

You know how you might take a photo every year on your birthday to see how you've changed? Longitudinal Design is kind of like that, but for scientific research.

With Longitudinal Design, instead of measuring something just once, researchers come back again and again, sometimes over many years, to see how things are going. This helps them understand not just what's happening, but why it's happening and how it changes over time.

This design really started to shine in the latter half of the 20th century, when researchers began to realize that some questions can't be answered in a hurry. Think about studies that look at how kids grow up, or research on how a certain medicine affects you over a long period. These aren't things you can rush.

The famous Framingham Heart Study , started in 1948, is a prime example. It's been studying heart health in a small town in Massachusetts for decades, and the findings have shaped what we know about heart disease.

Longitudinal Design Pros

So, what's to love about Longitudinal Design? First off, it's the go-to for studying change over time, whether that's how people age or how a forest recovers from a fire.

Longitudinal Design Cons

But it's not all sunshine and rainbows. Longitudinal studies take a lot of patience and resources. Plus, keeping track of participants over many years can be like herding cats—difficult and full of surprises.

Longitudinal Design Uses

Despite these challenges, longitudinal studies have been key in fields like psychology, sociology, and medicine. They provide the kind of deep, long-term insights that other designs just can't match.

So, if the True Experimental Design is the superstar quarterback, and the Quasi-Experimental Design is the flexible athlete, then the Factorial Design is the strategist, and the Longitudinal Design is the wise elder who has seen it all and has stories to tell.

6) Cross-Sectional Design

Now, let's flip the script and talk about Cross-Sectional Design, the polar opposite of the Longitudinal Design. If Longitudinal is the grand storyteller, think of Cross-Sectional as the snapshot photographer. It captures a single moment in time, like a selfie that you take to remember a fun day. Researchers using this design collect all their data at one point, providing a kind of "snapshot" of whatever they're studying.

In a Cross-Sectional Design, researchers look at multiple groups all at the same time to see how they're different or similar.

This design rose to popularity in the mid-20th century, mainly because it's so quick and efficient. Imagine wanting to know how people of different ages feel about a new video game. Instead of waiting for years to see how opinions change, you could just ask people of all ages what they think right now. That's Cross-Sectional Design for you—fast and straightforward.

You'll find this type of research everywhere from marketing studies to healthcare. For instance, you might have heard about surveys asking people what they think about a new product or political issue. Those are usually cross-sectional studies, aimed at getting a quick read on public opinion.

Cross-Sectional Design Pros

So, what's the big deal with Cross-Sectional Design? Well, it's the go-to when you need answers fast and don't have the time or resources for a more complicated setup.

Cross-Sectional Design Cons

Remember, speed comes with trade-offs. While you get your results quickly, those results are stuck in time. They can't tell you how things change or why they're changing, just what's happening right now.

Cross-Sectional Design Uses

Also, because they're so quick and simple, cross-sectional studies often serve as the first step in research. They give scientists an idea of what's going on so they can decide if it's worth digging deeper. In that way, they're a bit like a movie trailer, giving you a taste of the action to see if you're interested in seeing the whole film.

So, in our lineup of experimental designs, if True Experimental Design is the superstar quarterback and Longitudinal Design is the wise elder, then Cross-Sectional Design is like the speedy running back—fast, agile, but not designed for long, drawn-out plays.

7) Correlational Design

Next on our roster is the Correlational Design, the keen observer of the experimental world. Imagine this design as the person at a party who loves people-watching. They don't interfere or get involved; they just observe and take mental notes about what's going on.

In a correlational study, researchers don't change or control anything; they simply observe and measure how two variables relate to each other.

The correlational design has roots in the early days of psychology and sociology. Pioneers like Sir Francis Galton used it to study how qualities like intelligence or height could be related within families.

This design is all about asking, "Hey, when this thing happens, does that other thing usually happen too?" For example, researchers might study whether students who have more study time get better grades or whether people who exercise more have lower stress levels.

One of the most famous correlational studies you might have heard of is the link between smoking and lung cancer. Back in the mid-20th century, researchers started noticing that people who smoked a lot also seemed to get lung cancer more often. They couldn't say smoking caused cancer—that would require a true experiment—but the strong correlation was a red flag that led to more research and eventually, health warnings.

Correlational Design Pros

This design is great at proving that two (or more) things can be related. Correlational designs can help prove that more detailed research is needed on a topic. They can help us see patterns or possible causes for things that we otherwise might not have realized.

Correlational Design Cons

But here's where you need to be careful: correlational designs can be tricky. Just because two things are related doesn't mean one causes the other. That's like saying, "Every time I wear my lucky socks, my team wins." Well, it's a fun thought, but those socks aren't really controlling the game.

Correlational Design Uses

Despite this limitation, correlational designs are popular in psychology, economics, and epidemiology, to name a few fields. They're often the first step in exploring a possible relationship between variables. Once a strong correlation is found, researchers may decide to conduct more rigorous experimental studies to examine cause and effect.

So, if the True Experimental Design is the superstar quarterback and the Longitudinal Design is the wise elder, the Factorial Design is the strategist, and the Cross-Sectional Design is the speedster, then the Correlational Design is the clever scout, identifying interesting patterns but leaving the heavy lifting of proving cause and effect to the other types of designs.

8) Meta-Analysis

Last but not least, let's talk about Meta-Analysis, the librarian of experimental designs.

If other designs are all about creating new research, Meta-Analysis is about gathering up everyone else's research, sorting it, and figuring out what it all means when you put it together.

Imagine a jigsaw puzzle where each piece is a different study. Meta-Analysis is the process of fitting all those pieces together to see the big picture.

The concept of Meta-Analysis started to take shape in the late 20th century, when computers became powerful enough to handle massive amounts of data. It was like someone handed researchers a super-powered magnifying glass, letting them examine multiple studies at the same time to find common trends or results.

You might have heard of the Cochrane Reviews in healthcare . These are big collections of meta-analyses that help doctors and policymakers figure out what treatments work best based on all the research that's been done.

For example, if ten different studies show that a certain medicine helps lower blood pressure, a meta-analysis would pull all that information together to give a more accurate answer.

Meta-Analysis Pros

The beauty of Meta-Analysis is that it can provide really strong evidence. Instead of relying on one study, you're looking at the whole landscape of research on a topic.

Meta-Analysis Cons

However, it does have some downsides. For one, Meta-Analysis is only as good as the studies it includes. If those studies are flawed, the meta-analysis will be too. It's like baking a cake: if you use bad ingredients, it doesn't matter how good your recipe is—the cake won't turn out well.

Meta-Analysis Uses

Despite these challenges, meta-analyses are highly respected and widely used in many fields like medicine, psychology, and education. They help us make sense of a world that's bursting with information by showing us the big picture drawn from many smaller snapshots.

So, in our all-star lineup, if True Experimental Design is the quarterback and Longitudinal Design is the wise elder, the Factorial Design is the strategist, the Cross-Sectional Design is the speedster, and the Correlational Design is the scout, then the Meta-Analysis is like the coach, using insights from everyone else's plays to come up with the best game plan.

9) Non-Experimental Design

Now, let's talk about a player who's a bit of an outsider on this team of experimental designs—the Non-Experimental Design. Think of this design as the commentator or the journalist who covers the game but doesn't actually play.

In a Non-Experimental Design, researchers are like reporters gathering facts, but they don't interfere or change anything. They're simply there to describe and analyze.

Non-Experimental Design Pros

So, what's the deal with Non-Experimental Design? Its strength is in description and exploration. It's really good for studying things as they are in the real world, without changing any conditions.

Non-Experimental Design Cons

Because a non-experimental design doesn't manipulate variables, it can't prove cause and effect. It's like a weather reporter: they can tell you it's raining, but they can't tell you why it's raining.

The downside? Since researchers aren't controlling variables, it's hard to rule out other explanations for what they observe. It's like hearing one side of a story—you get an idea of what happened, but it might not be the complete picture.

Non-Experimental Design Uses

Non-Experimental Design has always been a part of research, especially in fields like anthropology, sociology, and some areas of psychology.

For instance, if you've ever heard of studies that describe how people behave in different cultures or what teens like to do in their free time, that's often Non-Experimental Design at work. These studies aim to capture the essence of a situation, like painting a portrait instead of taking a snapshot.

One well-known example you might have heard about is the Kinsey Reports from the 1940s and 1950s, which described sexual behavior in men and women. Researchers interviewed thousands of people but didn't manipulate any variables like you would in a true experiment. They simply collected data to create a comprehensive picture of the subject matter.

So, in our metaphorical team of research designs, if True Experimental Design is the quarterback and Longitudinal Design is the wise elder, Factorial Design is the strategist, Cross-Sectional Design is the speedster, Correlational Design is the scout, and Meta-Analysis is the coach, then Non-Experimental Design is the sports journalist—always present, capturing the game, but not part of the action itself.

10) Repeated Measures Design

Time to meet the Repeated Measures Design, the time traveler of our research team. If this design were a player in a sports game, it would be the one who keeps revisiting past plays to figure out how to improve the next one.

Repeated Measures Design is all about studying the same people or subjects multiple times to see how they change or react under different conditions.

The idea behind Repeated Measures Design isn't new; it's been around since the early days of psychology and medicine. You could say it's a cousin to the Longitudinal Design, but instead of looking at how things naturally change over time, it focuses on how the same group reacts to different things.

Imagine a study looking at how a new energy drink affects people's running speed. Instead of comparing one group that drank the energy drink to another group that didn't, a Repeated Measures Design would have the same group of people run multiple times—once with the energy drink, and once without. This way, you're really zeroing in on the effect of that energy drink, making the results more reliable.

Repeated Measures Design Pros

The strong point of Repeated Measures Design is that it's super focused. Because it uses the same subjects, you don't have to worry about differences between groups messing up your results.

Repeated Measures Design Cons

But the downside? Well, people can get tired or bored if they're tested too many times, which might affect how they respond.

Repeated Measures Design Uses

A famous example of this design is the "Little Albert" experiment, conducted by John B. Watson and Rosalie Rayner in 1920. In this study, a young boy was exposed to a white rat and other stimuli several times to see how his emotional responses changed. Though the ethical standards of this experiment are often criticized today, it was groundbreaking in understanding conditioned emotional responses.

In our metaphorical lineup of research designs, if True Experimental Design is the quarterback and Longitudinal Design is the wise elder, Factorial Design is the strategist, Cross-Sectional Design is the speedster, Correlational Design is the scout, Meta-Analysis is the coach, and Non-Experimental Design is the journalist, then Repeated Measures Design is the time traveler—always looping back to fine-tune the game plan.

11) Crossover Design

Next up is Crossover Design, the switch-hitter of the research world. If you're familiar with baseball, you'll know a switch-hitter is someone who can bat both right-handed and left-handed.

In a similar way, Crossover Design allows subjects to experience multiple conditions, flipping them around so that everyone gets a turn in each role.

This design is like the utility player on our team—versatile, flexible, and really good at adapting.

The Crossover Design has its roots in medical research and has been popular since the mid-20th century. It's often used in clinical trials to test the effectiveness of different treatments.

Crossover Design Pros

The neat thing about this design is that it allows each participant to serve as their own control group. Imagine you're testing two new kinds of headache medicine. Instead of giving one type to one group and another type to a different group, you'd give both kinds to the same people but at different times.

Crossover Design Cons

What's the big deal with Crossover Design? Its major strength is in reducing the "noise" that comes from individual differences. Since each person experiences all conditions, it's easier to see real effects. However, there's a catch. This design assumes that there's no lasting effect from the first condition when you switch to the second one. That might not always be true. If the first treatment has a long-lasting effect, it could mess up the results when you switch to the second treatment.

Crossover Design Uses

A well-known example of Crossover Design is in studies that look at the effects of different types of diets—like low-carb vs. low-fat diets. Researchers might have participants follow a low-carb diet for a few weeks, then switch them to a low-fat diet. By doing this, they can more accurately measure how each diet affects the same group of people.

In our team of experimental designs, if True Experimental Design is the quarterback and Longitudinal Design is the wise elder, Factorial Design is the strategist, Cross-Sectional Design is the speedster, Correlational Design is the scout, Meta-Analysis is the coach, Non-Experimental Design is the journalist, and Repeated Measures Design is the time traveler, then Crossover Design is the versatile utility player—always ready to adapt and play multiple roles to get the most accurate results.

12) Cluster Randomized Design

Meet the Cluster Randomized Design, the team captain of group-focused research. In our imaginary lineup of experimental designs, if other designs focus on individual players, then Cluster Randomized Design is looking at how the entire team functions.

This approach is especially common in educational and community-based research, and it's been gaining traction since the late 20th century.

Here's how Cluster Randomized Design works: Instead of assigning individual people to different conditions, researchers assign entire groups, or "clusters." These could be schools, neighborhoods, or even entire towns. This helps you see how the new method works in a real-world setting.

Imagine you want to see if a new anti-bullying program really works. Instead of selecting individual students, you'd introduce the program to a whole school or maybe even several schools, and then compare the results to schools without the program.

Cluster Randomized Design Pros

Why use Cluster Randomized Design? Well, sometimes it's just not practical to assign conditions at the individual level. For example, you can't really have half a school following a new reading program while the other half sticks with the old one; that would be way too confusing! Cluster Randomization helps get around this problem by treating each "cluster" as its own mini-experiment.

Cluster Randomized Design Cons

There's a downside, too. Because entire groups are assigned to each condition, there's a risk that the groups might be different in some important way that the researchers didn't account for. That's like having one sports team that's full of veterans playing against a team of rookies; the match wouldn't be fair.

Cluster Randomized Design Uses

A famous example is the research conducted to test the effectiveness of different public health interventions, like vaccination programs. Researchers might roll out a vaccination program in one community but not in another, then compare the rates of disease in both.

In our metaphorical research team, if True Experimental Design is the quarterback, Longitudinal Design is the wise elder, Factorial Design is the strategist, Cross-Sectional Design is the speedster, Correlational Design is the scout, Meta-Analysis is the coach, Non-Experimental Design is the journalist, Repeated Measures Design is the time traveler, and Crossover Design is the utility player, then Cluster Randomized Design is the team captain—always looking out for the group as a whole.

13) Mixed-Methods Design

Say hello to Mixed-Methods Design, the all-rounder or the "Renaissance player" of our research team.

Mixed-Methods Design uses a blend of both qualitative and quantitative methods to get a more complete picture, just like a Renaissance person who's good at lots of different things. It's like being good at both offense and defense in a sport; you've got all your bases covered!

Mixed-Methods Design is a fairly new kid on the block, becoming more popular in the late 20th and early 21st centuries as researchers began to see the value in using multiple approaches to tackle complex questions. It's the Swiss Army knife in our research toolkit, combining the best parts of other designs to be more versatile.

Here's how it could work: Imagine you're studying the effects of a new educational app on students' math skills. You might use quantitative methods like tests and grades to measure how much the students improve—that's the 'numbers part.'

But you also want to know how the students feel about math now, or why they think they got better or worse. For that, you could conduct interviews or have students fill out journals—that's the 'story part.'

Mixed-Methods Design Pros

So, what's the scoop on Mixed-Methods Design? The strength is its versatility and depth; you're not just getting numbers or stories, you're getting both, which gives a fuller picture.

Mixed-Methods Design Cons

But, it's also more challenging. Imagine trying to play two sports at the same time! You have to be skilled in different research methods and know how to combine them effectively.

Mixed-Methods Design Uses

A high-profile example of Mixed-Methods Design is research on climate change. Scientists use numbers and data to show temperature changes (quantitative), but they also interview people to understand how these changes are affecting communities (qualitative).

In our team of experimental designs, if True Experimental Design is the quarterback, Longitudinal Design is the wise elder, Factorial Design is the strategist, Cross-Sectional Design is the speedster, Correlational Design is the scout, Meta-Analysis is the coach, Non-Experimental Design is the journalist, Repeated Measures Design is the time traveler, Crossover Design is the utility player, and Cluster Randomized Design is the team captain, then Mixed-Methods Design is the Renaissance player—skilled in multiple areas and able to bring them all together for a winning strategy.

14) Multivariate Design

Now, let's turn our attention to Multivariate Design, the multitasker of the research world.

If our lineup of research designs were like players on a basketball court, Multivariate Design would be the player dribbling, passing, and shooting all at once. This design doesn't just look at one or two things; it looks at several variables simultaneously to see how they interact and affect each other.

Multivariate Design is like baking a cake with many ingredients. Instead of just looking at how flour affects the cake, you also consider sugar, eggs, and milk all at once. This way, you understand how everything works together to make the cake taste good or bad.

Multivariate Design has been a go-to method in psychology, economics, and social sciences since the latter half of the 20th century. With the advent of computers and advanced statistical software, analyzing multiple variables at once became a lot easier, and Multivariate Design soared in popularity.

Multivariate Design Pros

So, what's the benefit of using Multivariate Design? Its power lies in its complexity. By studying multiple variables at the same time, you can get a really rich, detailed understanding of what's going on.

Multivariate Design Cons

But that complexity can also be a drawback. With so many variables, it can be tough to tell which ones are really making a difference and which ones are just along for the ride.

Multivariate Design Uses

Imagine you're a coach trying to figure out the best strategy to win games. You wouldn't just look at how many points your star player scores; you'd also consider assists, rebounds, turnovers, and maybe even how loud the crowd is. A Multivariate Design would help you understand how all these factors work together to determine whether you win or lose.

A well-known example of Multivariate Design is in market research. Companies often use this approach to figure out how different factors—like price, packaging, and advertising—affect sales. By studying multiple variables at once, they can find the best combination to boost profits.

In our metaphorical research team, if True Experimental Design is the quarterback, Longitudinal Design is the wise elder, Factorial Design is the strategist, Cross-Sectional Design is the speedster, Correlational Design is the scout, Meta-Analysis is the coach, Non-Experimental Design is the journalist, Repeated Measures Design is the time traveler, Crossover Design is the utility player, Cluster Randomized Design is the team captain, and Mixed-Methods Design is the Renaissance player, then Multivariate Design is the multitasker—juggling many variables at once to get a fuller picture of what's happening.

15) Pretest-Posttest Design

Let's introduce Pretest-Posttest Design, the "Before and After" superstar of our research team. You've probably seen those before-and-after pictures in ads for weight loss programs or home renovations, right?

Well, this design is like that, but for science! Pretest-Posttest Design checks out what things are like before the experiment starts and then compares that to what things are like after the experiment ends.

This design is one of the classics, a staple in research for decades across various fields like psychology, education, and healthcare. It's so simple and straightforward that it has stayed popular for a long time.

In Pretest-Posttest Design, you measure your subject's behavior or condition before you introduce any changes—that's your "before" or "pretest." Then you do your experiment, and after it's done, you measure the same thing again—that's your "after" or "posttest."

Pretest-Posttest Design Pros

What makes Pretest-Posttest Design special? It's pretty easy to understand and doesn't require fancy statistics.

Pretest-Posttest Design Cons

But there are some pitfalls. For example, what if the kids in our math example get better at multiplication just because they're older or because they've taken the test before? That would make it hard to tell if the program is really effective or not.

Pretest-Posttest Design Uses

Let's say you're a teacher and you want to know if a new math program helps kids get better at multiplication. First, you'd give all the kids a multiplication test—that's your pretest. Then you'd teach them using the new math program. At the end, you'd give them the same test again—that's your posttest. If the kids do better on the second test, you might conclude that the program works.

One famous use of Pretest-Posttest Design is in evaluating the effectiveness of driver's education courses. Researchers will measure people's driving skills before and after the course to see if they've improved.

16) Solomon Four-Group Design

Next up is the Solomon Four-Group Design, the "chess master" of our research team. This design is all about strategy and careful planning. Named after Richard L. Solomon who introduced it in the 1940s, this method tries to correct some of the weaknesses in simpler designs, like the Pretest-Posttest Design.

Here's how it rolls: The Solomon Four-Group Design uses four different groups to test a hypothesis. Two groups get a pretest, then one of them receives the treatment or intervention, and both get a posttest. The other two groups skip the pretest, and only one of them receives the treatment before they both get a posttest.

Sound complicated? It's like playing 4D chess; you're thinking several moves ahead!

Solomon Four-Group Design Pros

What's the pro and con of the Solomon Four-Group Design? On the plus side, it provides really robust results because it accounts for so many variables.

Solomon Four-Group Design Cons

The downside? It's a lot of work and requires a lot of participants, making it more time-consuming and costly.

Solomon Four-Group Design Uses

Let's say you want to figure out if a new way of teaching history helps students remember facts better. Two classes take a history quiz (pretest), then one class uses the new teaching method while the other sticks with the old way. Both classes take another quiz afterward (posttest).

Meanwhile, two more classes skip the initial quiz, and then one uses the new method before both take the final quiz. Comparing all four groups will give you a much clearer picture of whether the new teaching method works and whether the pretest itself affects the outcome.

The Solomon Four-Group Design is less commonly used than simpler designs but is highly respected for its ability to control for more variables. It's a favorite in educational and psychological research where you really want to dig deep and figure out what's actually causing changes.

17) Adaptive Designs

Now, let's talk about Adaptive Designs, the chameleons of the experimental world.

Imagine you're a detective, and halfway through solving a case, you find a clue that changes everything. You wouldn't just stick to your old plan; you'd adapt and change your approach, right? That's exactly what Adaptive Designs allow researchers to do.

In an Adaptive Design, researchers can make changes to the study as it's happening, based on early results. In a traditional study, once you set your plan, you stick to it from start to finish.

Adaptive Design Pros

This method is particularly useful in fast-paced or high-stakes situations, like developing a new vaccine in the middle of a pandemic. The ability to adapt can save both time and resources, and more importantly, it can save lives by getting effective treatments out faster.

Adaptive Design Cons

But Adaptive Designs aren't without their drawbacks. They can be very complex to plan and carry out, and there's always a risk that the changes made during the study could introduce bias or errors.

Adaptive Design Uses

Adaptive Designs are most often seen in clinical trials, particularly in the medical and pharmaceutical fields.

For instance, if a new drug is showing really promising results, the study might be adjusted to give more participants the new treatment instead of a placebo. Or if one dose level is showing bad side effects, it might be dropped from the study.

The best part is, these changes are pre-planned. Researchers lay out in advance what changes might be made and under what conditions, which helps keep everything scientific and above board.

In terms of applications, besides their heavy usage in medical and pharmaceutical research, Adaptive Designs are also becoming increasingly popular in software testing and market research. In these fields, being able to quickly adjust to early results can give companies a significant advantage.

Adaptive Designs are like the agile startups of the research world—quick to pivot, keen to learn from ongoing results, and focused on rapid, efficient progress. However, they require a great deal of expertise and careful planning to ensure that the adaptability doesn't compromise the integrity of the research.

18) Bayesian Designs

Next, let's dive into Bayesian Designs, the data detectives of the research universe. Named after Thomas Bayes, an 18th-century statistician and minister, this design doesn't just look at what's happening now; it also takes into account what's happened before.

Imagine if you were a detective who not only looked at the evidence in front of you but also used your past cases to make better guesses about your current one. That's the essence of Bayesian Designs.

Bayesian Designs are like detective work in science. As you gather more clues (or data), you update your best guess on what's really happening. This way, your experiment gets smarter as it goes along.

In the world of research, Bayesian Designs are most notably used in areas where you have some prior knowledge that can inform your current study. For example, if earlier research shows that a certain type of medicine usually works well for a specific illness, a Bayesian Design would include that information when studying a new group of patients with the same illness.

Bayesian Design Pros

One of the major advantages of Bayesian Designs is their efficiency. Because they use existing data to inform the current experiment, often fewer resources are needed to reach a reliable conclusion.

Bayesian Design Cons

However, they can be quite complicated to set up and require a deep understanding of both statistics and the subject matter at hand.

Bayesian Design Uses

Bayesian Designs are highly valued in medical research, finance, environmental science, and even in Internet search algorithms. Their ability to continually update and refine hypotheses based on new evidence makes them particularly useful in fields where data is constantly evolving and where quick, informed decisions are crucial.

Here's a real-world example: In the development of personalized medicine, where treatments are tailored to individual patients, Bayesian Designs are invaluable. If a treatment has been effective for patients with similar genetics or symptoms in the past, a Bayesian approach can use that data to predict how well it might work for a new patient.

This type of design is also increasingly popular in machine learning and artificial intelligence. In these fields, Bayesian Designs help algorithms "learn" from past data to make better predictions or decisions in new situations. It's like teaching a computer to be a detective that gets better and better at solving puzzles the more puzzles it sees.

19) Covariate Adaptive Randomization

Now let's turn our attention to Covariate Adaptive Randomization, which you can think of as the "matchmaker" of experimental designs.

Picture a soccer coach trying to create the most balanced teams for a friendly match. They wouldn't just randomly assign players; they'd take into account each player's skills, experience, and other traits.

Covariate Adaptive Randomization is all about creating the most evenly matched groups possible for an experiment.

In traditional randomization, participants are allocated to different groups purely by chance. This is a pretty fair way to do things, but it can sometimes lead to unbalanced groups.

Imagine if all the professional-level players ended up on one soccer team and all the beginners on another; that wouldn't be a very informative match! Covariate Adaptive Randomization fixes this by using important traits or characteristics (called "covariates") to guide the randomization process.

Covariate Adaptive Randomization Pros

The benefits of this design are pretty clear: it aims for balance and fairness, making the final results more trustworthy.

Covariate Adaptive Randomization Cons

But it's not perfect. It can be complex to implement and requires a deep understanding of which characteristics are most important to balance.

Covariate Adaptive Randomization Uses

This design is particularly useful in medical trials. Let's say researchers are testing a new medication for high blood pressure. Participants might have different ages, weights, or pre-existing conditions that could affect the results.

Covariate Adaptive Randomization would make sure that each treatment group has a similar mix of these characteristics, making the results more reliable and easier to interpret.

In practical terms, this design is often seen in clinical trials for new drugs or therapies, but its principles are also applicable in fields like psychology, education, and social sciences.

For instance, in educational research, it might be used to ensure that classrooms being compared have similar distributions of students in terms of academic ability, socioeconomic status, and other factors.

Covariate Adaptive Randomization is like the wise elder of the group, ensuring that everyone has an equal opportunity to show their true capabilities, thereby making the collective results as reliable as possible.

20) Stepped Wedge Design

Let's now focus on the Stepped Wedge Design, a thoughtful and cautious member of the experimental design family.

Imagine you're trying out a new gardening technique, but you're not sure how well it will work. You decide to apply it to one section of your garden first, watch how it performs, and then gradually extend the technique to other sections. This way, you get to see its effects over time and across different conditions. That's basically how Stepped Wedge Design works.

In a Stepped Wedge Design, all participants or clusters start off in the control group, and then, at different times, they 'step' over to the intervention or treatment group. This creates a wedge-like pattern over time where more and more participants receive the treatment as the study progresses. It's like rolling out a new policy in phases, monitoring its impact at each stage before extending it to more people.

Stepped Wedge Design Pros

The Stepped Wedge Design offers several advantages. Firstly, it allows for the study of interventions that are expected to do more good than harm, which makes it ethically appealing.

Secondly, it's useful when resources are limited and it's not feasible to roll out a new treatment to everyone at once. Lastly, because everyone eventually receives the treatment, it can be easier to get buy-in from participants or organizations involved in the study.

Stepped Wedge Design Cons

However, this design can be complex to analyze because it has to account for both the time factor and the changing conditions in each 'step' of the wedge. And like any study where participants know they're receiving an intervention, there's the potential for the results to be influenced by the placebo effect or other biases.

Stepped Wedge Design Uses

This design is particularly useful in health and social care research. For instance, if a hospital wants to implement a new hygiene protocol, it might start in one department, assess its impact, and then roll it out to other departments over time. This allows the hospital to adjust and refine the new protocol based on real-world data before it's fully implemented.

In terms of applications, Stepped Wedge Designs are commonly used in public health initiatives, organizational changes in healthcare settings, and social policy trials. They are particularly useful in situations where an intervention is being rolled out gradually and it's important to understand its impacts at each stage.

21) Sequential Design

Next up is Sequential Design, the dynamic and flexible member of our experimental design family.

Imagine you're playing a video game where you can choose different paths. If you take one path and find a treasure chest, you might decide to continue in that direction. If you hit a dead end, you might backtrack and try a different route. Sequential Design operates in a similar fashion, allowing researchers to make decisions at different stages based on what they've learned so far.

In a Sequential Design, the experiment is broken down into smaller parts, or "sequences." After each sequence, researchers pause to look at the data they've collected. Based on those findings, they then decide whether to stop the experiment because they've got enough information, or to continue and perhaps even modify the next sequence.

Sequential Design Pros

This allows for a more efficient use of resources, as you're only continuing with the experiment if the data suggests it's worth doing so.

One of the great things about Sequential Design is its efficiency. Because you're making data-driven decisions along the way, you can often reach conclusions more quickly and with fewer resources.

Sequential Design Cons

However, it requires careful planning and expertise to ensure that these "stop or go" decisions are made correctly and without bias.

Sequential Design Uses

In terms of its applications, besides healthcare and medicine, Sequential Design is also popular in quality control in manufacturing, environmental monitoring, and financial modeling. In these areas, being able to make quick decisions based on incoming data can be a big advantage.

This design is often used in clinical trials involving new medications or treatments. For example, if early results show that a new drug has significant side effects, the trial can be stopped before more people are exposed to it.

On the flip side, if the drug is showing promising results, the trial might be expanded to include more participants or to extend the testing period.

Think of Sequential Design as the nimble athlete of experimental designs, capable of quick pivots and adjustments to reach the finish line in the most effective way possible. But just like an athlete needs a good coach, this design requires expert oversight to make sure it stays on the right track.

22) Field Experiments

Last but certainly not least, let's explore Field Experiments—the adventurers of the experimental design world.

Picture a scientist leaving the controlled environment of a lab to test a theory in the real world, like a biologist studying animals in their natural habitat or a social scientist observing people in a real community. These are Field Experiments, and they're all about getting out there and gathering data in real-world settings.

Field Experiments embrace the messiness of the real world, unlike laboratory experiments, where everything is controlled down to the smallest detail. This makes them both exciting and challenging.

Field Experiment Pros

On one hand, the results often give us a better understanding of how things work outside the lab.

While Field Experiments offer real-world relevance, they come with challenges like controlling for outside factors and the ethical considerations of intervening in people's lives without their knowledge.

Field Experiment Cons

On the other hand, the lack of control can make it harder to tell exactly what's causing what. Yet, despite these challenges, they remain a valuable tool for researchers who want to understand how theories play out in the real world.

Field Experiment Uses

Let's say a school wants to improve student performance. In a Field Experiment, they might change the school's daily schedule for one semester and keep track of how students perform compared to another school where the schedule remained the same.

Because the study is happening in a real school with real students, the results could be very useful for understanding how the change might work in other schools. But since it's the real world, lots of other factors—like changes in teachers or even the weather—could affect the results.

Field Experiments are widely used in economics, psychology, education, and public policy. For example, you might have heard of the famous "Broken Windows" experiment in the 1980s that looked at how small signs of disorder, like broken windows or graffiti, could encourage more serious crime in neighborhoods. This experiment had a big impact on how cities think about crime prevention.

From the foundational concepts of control groups and independent variables to the sophisticated layouts like Covariate Adaptive Randomization and Sequential Design, it's clear that the realm of experimental design is as varied as it is fascinating.

We've seen that each design has its own special talents, ideal for specific situations. Some designs, like the Classic Controlled Experiment, are like reliable old friends you can always count on.

Others, like Sequential Design, are flexible and adaptable, making quick changes based on what they learn. And let's not forget the adventurous Field Experiments, which take us out of the lab and into the real world to discover things we might not see otherwise.

Choosing the right experimental design is like picking the right tool for the job. The method you choose can make a big difference in how reliable your results are and how much people will trust what you've discovered. And as we've learned, there's a design to suit just about every question, every problem, and every curiosity.

So the next time you read about a new discovery in medicine, psychology, or any other field, you'll have a better understanding of the thought and planning that went into figuring things out. Experimental design is more than just a set of rules; it's a structured way to explore the unknown and answer questions that can change the world.

Related posts:

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• 40+ Famous Psychologists (Images + Biographies)
• 11+ Psychology Experiment Ideas (Goals + Methods)
• The Little Albert Experiment
• 41+ White Collar Job Examples (Salary + Path)

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On Experiments and Experience

In life and the lab, trials are an essential part of exploration and discovery.

By Jennifer Burrows Nielson (BS ’88) in the Summer 2015 Issue

When I was a brand-new chemistry graduate student at the University of California, San Diego, my faculty advisor, Charlie Perrin, gave me the relatively easy task of replicating the experiments of a student who was leaving our lab. The results from that project were going to be published in a top journal in my field.

When I finished the experiments, my results were the opposite of the original findings. I repeated the experiments several times, but each time the results didn’t match—and I began to panic. My failure to replicate felt like evidence that I was terrible in the lab. I took my results to my advisor, and he was surprised. He suggested a series of modified molecules on which I could repeat similar experiments.

I worked hard. I purified materials. I read techniques in the literature. I did a mountain of experiments. I talked about ideas with my favorite chemistry friend, Julie Manning Matheson (BA ’88), and at the end of a long day I would come home and worry out loud to my husband, Daniel L. Nielson (BA ’88).

In the end what we learned was that the original results were inaccurate. Eventually, we published a paper in the same journal, retracting the first claims and proposing a new conclusion. In fact, the title changed from “Symmetries of Hydrogen Bonds” to “Asymmetry of Hydrogen Bonds.”

In the process Charlie Perrin became one of my heroes. He demonstrated that he valued learning truth over protecting his reputation. Every time I entered his office with new ideas or unexpected results, he welcomed them. He felt that even unexpected results taught us something.

I learned so much from this experience that has shaped me over the years—including that ice cream soothes my soul after a long day. More important, I learned that experiments help us gain truth, that we can become stronger from struggles, that meaningful results require a lot of time and effort, and that working with others is essential. I believe that the purpose of life experiences—which we might also call life experiments—is to help us grow and become more Christlike.

Try the Experiment

When our son Rob graduated from diapers at age 2, he got his first pair of briefs, emblazoned with the Spiderman logo. Excited, he asked, “Does this mean I can climb up walls now?” He tested his theory, and he learned he could not climb walls, but he confirmed a number of times that he could bounce off them.

Theory—in life or in the lab—is not enough. Experimenting is where theory meets reality. Experiments teach us whether a theory explains reality or needs to be revised or discarded. In religion, doctrine remains theory in our minds until we show our belief in the doctrine by acting. Amulek taught this principle to the poor among the Zoramites, exhorting them to “plant the word in your hearts, that ye may try the experiment of its goodness” ( Alma 34:4 ; emphasis added).

A good experiment can make learning concrete and teach us truth. I am seeing firsthand the value of experiments in my current chemistry-education research in Uganda. Last year Makerere University—the largest university in East Africa and the most prestigious in Uganda—had only two students declare chemistry as their major. The year before there was only one. What could be the reason for this? Here’s a clue: students in Uganda are required to study four to six years of chemistry before they finish secondary school, yet few of them have opportunities to learn chemistry principles through hands-on experience—through experimentation. Many secondary schools lack the adequate equipment and supplies for chemistry labs and the facilities to handle lab waste. So for most students, chemistry is pure theory and rote memorization. Consequently, many of the students come to see it as pointless and too difficult.

“The words EXPERIMENT and EXPERIENCE have the same Latin root: they both come from the word EXPERIOR, which means to GAIN KNOWLEDGE THROUGH REPEATED TRIALS.”

As I have worked in Uganda over the past few summers, I have seen the need for students to experience science hands-on to make the chemistry concepts come alive and become meaningful. My research team facilitates workshops designed to help secondary school teachers incorporate simple water-based experiments into their classes and labs. The team emphasizes exploration and experience, discovery and development.

The words experiment and experience have the same Latin root: they both come from the word experior, which means to gain knowledge through repeated trials. For most of us, the word trial represents the difficult, sometimes horrendous, experiences we have in life. But in the scientific world, the word trial has positive connotations. It refers to experiments repeated in order to learn something valuable. For example, a clinical trial can be used to study the effects of a new drug or medical procedure. In science, then, the word trial is not associated with the difficult parts of the experiment; it is the experiment.

Interestingly, the same Latin root is in the word peritus, or “tested,” which is related to the word peril, reminding us that there are risks in experiments. We often don’t find the results we would like, or there are sometimes unintended consequences, like an explosion in the lab. Yet it is through experimental trials that scientists collect enough data points to see patterns in their work and reveal truths about the world.

A sufficient number of trials gives power to an experiment. Power in this context refers to statistical power, which is derived from the number of observations and is one of the factors that gives us confidence in an experiment’s results. Another important factor in experimental trials is the range of variables or conditions. Greater range increases the probability of accurate results.

The Lord’s plan—the plan of salvation—provides both power and range as we learn through a multitude of temporal and spiritual experiences—not simply for the sake of gaining knowledge but also to develop the capacity to do and become. By contrast, you might describe the plan the adversary put forth—a plan in which we would always be forced to obey—as only one impoverished experiment. Satan’s plan had neither power nor range.

I am grateful for the opportunity the plan of salvation gives me to practice and continually improve and to learn truths about what I am capable of and where I need to change. Power comes when we see all our experiences—often trials in both senses of the word—simply as varied opportunities to practice faith, patience, resilience, love, service, and forgiveness. Sure, I can forgive when it is my sister, but am I capable of forgiving when it is my brother? (I have six.) Or when I am tired, when I am angry, when I am busy, when I am wronged? Every experience in life can become another trial run, giving us power to discover the truth about our lives and gain insight into how we can change to become more like our Savior.

One of my favorite missionary companions in Brazil showed me how difficult trials can provide perspective. Sister Adriana was a convert who had joined the Church at age 16. Growing up in a family that owned a bar, she had started drinking at an early age and become addicted. She told me that giving up alcohol was the hardest thing she had ever done. When we taught investigators the Word of Wisdom, I could certainly share my witness of its truth, but she would share her experience about craving alcohol and then testify that she would rather feel the Spirit, and she couldn’t do both. She had felt redemption from the Savior’s Atonement in this part of her life, and she could testify with power.

That is not to say that you have to experience everything to find truth and fulfill your potential. You don’t have to experiment with things that draw you away from God. Thankfully, our own experiences are not the only ones we have to rely on. This is one of the reasons we pass down wisdom from generation to generation through family and gospel stories. Likewise, when I listened to my companion’s testimony of the Word of Wisdom, it confirmed my own beliefs without me having to experience what she went through. In the words of Sir Isaac Newton, “If I have seen farther, it is by standing on the shoulders of giants.”¹

Stronger from Struggles

There is a saying that “the truth will set you free, but first it will make you miserable.” These words sure feel true sometimes; however, the gospel allows us to see trials as more than mere hardship but as a way to accumulate knowledge. Christ gives us the power to make good choices, the power to repent and begin again after making bad choices, and the power to identify truths from our experiences. President Howard W. Hunter taught, “If our lives and our faith are centered upon Jesus Christ and his restored gospel, nothing can ever go permanently wrong.”² With the Atonement my mistakes do not become permanent but can instead serve as another trial run as I learn how to become like Him.

Through the Atonement, even a horrible trial can turn from tragedy into victory. Remember what the Lord told Joseph Smith when he was in Liberty Jail. After describing all the ways in which the world could—and would—turn against Joseph, He then counseled: “Know thou, my son, that all these things shall give thee experience, and shall be for thy good” ( D&C 122:7 ; emphasis added; see verses 1–7). We can choose to see even hard experiences as opportunities to live and experiment and grow.

So how do we go about learning from and coming closer to Christ through our life experiments?

Reverend Thomas Bayes, the patron saint of statisticians, proposed a method for updating prior knowledge with newer experimental results.³ If my daily focus is to be a good driver and a kind person, a single incident of distractedly cutting someone off shouldn’t have sufficient weight to convince me that I am a bad driver. But it is a valuable data point that challenges me to renew my efforts to be more conscientious in my driving and to react charitably when others cut me off. However, if in my search for truth I find patterns in my behavior that do not fit with my view of myself, that evidence needs to be given more weight as I look to make necessary changes.

Professor Carol Dweck at Stanford University has spent 25 years researching how people’s self-concept matters in how they react to disappointment and failure. What do they do with results they don’t like? In one of her seminal studies she gave visual IQ tests to fifth graders and then randomly assigned what type of feedback each was given. In one group the students were told they had performed well and were praised for their intelligence. In the other group the students were told they had performed well and were praised for their hard work.

Next the children were given opportunities to practice different types of questions, and the students who had been praised for their effort overwhelmingly picked harder problems than the students praised for being smart. Dweck’s team then gave the fifth graders a seventh-grade IQ test, which, predictably, they all bombed. But the kids who had been praised for effort performed better than those who had been praised for their intelligence. This makes sense in retrospect, I suppose, given how the different groups had practiced. But then Dweck’s team did something especially clever: they administered the same fifth-grade test the children had all aced earlier. Again, the effort-praised children outperformed the intelligence-praised ones. But here is the surprising thing: the kids praised for being smart actually did worse than they had in the first round of testing. It was almost as if they had grown dumber. Once they no longer believed they were smart, they weren’t.⁴

Dweck has proposed that there are two basic mind-sets: a growth mind-set and a fixed mind-set.⁵ The assumption of those with a growth mind-set is that intelligence, creativity, artistic ability, and other traits are flexible, not frozen, and that one can increase them with practice. The assumption of those with a fixed mind-set is that traits are inherent and cannot be changed. The problem with the fixed mind-set is the belief that a negative outcome is a reflection on a person’s very nature. If I fail an exam, this mind-set says it is because I am not intelligent. In contrast, a person with the growth mind-set sees mistakes and failures as data points that can be used as Reverend Bayes proposed: to update prior knowledge to improve.

Our daughter Abigail C. Nielson (’20) is a talented runner. When she was a freshman in high school she became very focused on her performance. She feared failing because that would mean she wasn’t talented. One particularly hot fall afternoon she chose not to run in a meet because it just seemed too hard for her to run well. In contrast, by her senior year she used each meet, regardless of circumstances, to learn how she could improve. She scored in every race. She ended up as her team’s most consistent runner, placing better at nearly every meet, and she ran in the state championship. During her high school years, Abi had shifted from a fixed mind-set to a growth mind-set.

The good news, which Abi’s experience and Dweck’s subsequent research show, is it is possible to develop a growth mind-set and come to see yourself more as a work in progress who will improve with time and effort. I have seen many of my students develop more of a growth mind-set while learning chemistry. The really “good news”—the gōdspel (Old English), or gospel—is that Christ’s Atonement is very real, and that reality means we are not fixed but can always change and grow.

Hard Things with Help

Many of my own life experiments have been possible because of the people with whom I collaborate. For years our family motto was “Nielsons do hard things.” (You can imagine that our kids have not always been fond of the family motto.) However, we were rescued so many times during our first summer in Africa that we decided to update our motto: “Nielsons do hard things with help from God and others.”

At one point I was traveling in rural Uganda with my friend Kristyn Thompson Allred (BA ’89, MA ’90) to meet the organizer of a women’s co-op. It was raining hard, and the streets were not paved. By the time we arrived at the house, our feet were muddy. But I hesitated to take off my shoes to enter the house. These were fairly expensive walking sandals; I had bought them specifically because I knew I would be walking a lot in Africa that summer. With some anxiety I left them on the front porch.

“For God hath not given us THE SPIRIT OF FEAR, but of POWER, and of LOVE, and of A SOUND MIND.” —2 TIM. 1:7

When I stepped into the house I was astonished to see a paper on the refrigerator that read, “As Sisters in Zion.” Kristyn and I starting singing, and then a lilting voice joined us from the other room. I then noticed a picture of the First Presidency of the Church on the wall. We were in this little slice of heaven. Our new friend greeted us with the traditional and gracious Ugandan greeting “You are welcome.” And we responded by saying, “Thank you”—the opposite of what we do in the United States. This woman, it turned out, was a member of the Mukono Ward, and her husband was the bishop. She told us her story, and we met her kids. It was a glorious hour.

When we left the house, however, my soul sank when I saw that my shoes were gone. All those lovely feelings fled. Then, from around the corner of the house, a neighbor appeared, holding my shoes, now clean. It must have taken her the whole hour to remove the caked-on mud. She simply said, “You are welcome.” Those shoes mattered to me right then only because they had given me the experience of seeing the love of God and the goodness of people. I realized again that any hard thing I have done really has come through the help of God and others.

Recently one of my students came to me distraught over failing a midterm. We discussed several ways she might improve: taking the practice exam as if it were real, forming a study group, teaching the principles to others, and trying more problems. She listened, she adjusted, and she aced the next midterm. Later a different student expressed dismay at her performance on the midterm. The first student overheard her and immediately invited the discouraged classmate to join her study group and learn from the group’s collective experience. With love and help from her peers, my student could succeed in this hard endeavor.

Embrace Experience Without Fear

There will be many times when we have an experience we don’t want. So what can we do? May I suggest (with apologies to Stephen Stills), if you can’t be with the experience you love, Honey, love the experience you’re with.

In 2011 Rabbi Ronnie Cahana had a stroke that affected his brain stem. The effects of the stroke progressed slowly enough that he was aware as his body gradually became paralyzed, starting from his legs and traveling up to just below his eyes. The condition is known as locked-in syndrome. To communicate, family and friends would say the alphabet and he would blink when they got to the right letter, thereby spelling out a message.

Rabbi Cahana’s reaction to his paralysis was incredible. He spent hours pondering the beauty of God and life, wondering that he could experience such an exceptional state. He said that at night his mind would soar and he would be in motion, “swirling and twirling” above the ground. Blinking his eyes, he wrote letters and sermons sharing his experience. He declared, “I want you to know that this too, is healige (holy in Yiddish). I am in a broken place, but there is holy work to be done.”⁶ His willingness to search for truths in this trial helped him to transcend his misery.

In a TEDMED talk about Rabbi Cahana’s experience, his daughter said that the family cocooned him in love.⁷ He imagined moving his fingers while his loving family physically moved them in therapy. And then his body rekindled. Slowly he began to feel electrical sensations in his arms. He eventually regained enough feeling to breathe on his own and to talk. Every day he witnessed another miracle: as his abilities developed again like a baby’s, he observed it with all the experience of a 57-year-old mind and felt wonder and gratitude. He used his new understanding of truth to grow and was, remarkably, not afraid. The truth had set him free.

“He SUFFERED and DIED for us that we might EXPERIMENT and LIVE.”

If we are not afraid, our life experiments can be tools to learn truth and to make changes. The pioneering chemist Marie Curie believed that “nothing in life is to be feared—it is only to be understood.”⁸ My daughter Catherine A. Nielson (’15) recently took a class studying Mormon women, and she shared with me the story of another pioneer: Jean Rio Griffiths Baker, who, like many new converts from England, had to face an ocean of unknowns to travel to the United States to be with the Saints. In 1851, before she set out to cross the plains to Utah, she wrote in her journal, “The future will most likely be an account of trials, difficulties, and privations such as at present I have no idea of, so as to be able to provide against them. But as you are aware I am not one to go through the world with my eyes shut.”⁹

Paul taught us how to approach life experiences with confidence, using the Savior’s Atonement. One of my favorite scriptures is 2 Tim. 1:7 , because of the three gifts from God that are specifically mentioned: “For God hath not given us the spirit of fear; but of power, and of love, and of a sound mind.”

Our earth life is a unique time for exploration, experience, and discovery. Christ Himself showed us the importance of obtaining a body and experiencing life. Why couldn’t Christ just study the plan of salvation and learn what His role was in the Atonement? Couldn’t He just know all things? Instead He chose to come to earth. He experienced the rough waves in a ship and the calming power of the priesthood during a storm. He experienced the love and kindness of His mother and father, the gentleness of the woman who washed His feet with her tears, the gratitude of a leper He had healed, and the grief of friends when Lazarus died. He experienced the tenderness of Mary weeping for Him when she did not find Him in the tomb. He experienced Gethsemane, the cross, and cruelty. It wasn’t enough to know theoretically; He experienced the reality of mortality that He might know and understand what we experience. He suffered and died for us that we might experiment and live.

I share my witness of Jesus Christ and His Atonement. With Christ’s help we can repent; we can change and become the person God wants us to be. Let us use our life experiments to turn theory into reality—with Christ’s help.

This article is adapted from a BYU devotional address given by Jennifer B. Nielson, a BYU professor of chemistry and biochemistry, on March 3, 2015. The full text and video are available at speeches.byu.edu .

• Sir Isaac Newton, in David Brewster, Memoirs of the Life, Writings, and Discoveries of Sir Isaac Newton, vol. 1 (Edinburgh: Thomas Constable and Company, 1855), p. 142.
• Howard W. Hunter, “Fear Not, Little Flock,” BYU devotional address, March 14, 1989.
• See Thomas Bayes, “An Essay Towards Solving a Problem in the Doctrine of Chances,” Philosophical Transactions of the Royal Society of London 53 (1763): pp. 370–418.
• See Claudia M. Mueller and Carol S. Dweck, “Praise for Intelligence Can Undermine Children’s Motivation and Performance,” Journal of Personality and Social Psychology 75, no. 1 (1998): pp. 33–52.
• See Carol Dweck, Mindset: The New Psychology of Success (New York: Random House, 2006).
• Ronnie Cahana, quoted in Shayne Vitemb, “Rabbi Ronnie Cahana, Broken, but with Holy Work to Do,” Jewish Herald-Voice, May 31, 2012.
• See Kitra Cahana, “My Father, Locked in His Body but Soaring Free,” talk given at TEDMED 2014, San Francisco, https://tedmed.com/talks/show?id=292955 .
• Marie Curie, quoted in Barbara Goldsmith, Obsessive Genius: The Inner World of Marie Curie (New York: W. W. Norton, 2005), p. 15.
• Kenneth W. Godfrey, Audrey M. Godfrey, and Jill Mulvay Derr, Women’s Voices: An Untold History of the Latter-day Saints, 1830–1900 (Salt Lake City: Deseret Book, 1982), p. 221; see also pp. 203–21.

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• Four Real Life Chemistry Experiments You Can See Right Now
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Survival Guide: A Level Chemistry

The chemistry behind the tasty flavours of sushi.

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As students, we often times get so distracted with studying and learning as much as we can that we don’t take the time to actually enjoy the subject. A and O level Chemistry is a prime example. Here at Julian Chemistry, we not only strive to help students succeed in Chemistry learning , but also develop an enjoyment for the subject while attending our Chemistry tuition classes. We know it can be easy to get overwhelmed in memorizing chemical equations or acids and bases, that we don’t notice these reactions and key examples right in front of us. It’s the real life examples of chemistry that make it so cool! In this article, we’d like to show you just a few examples of chemistry in our everyday lives that will make you excited to learn more.

Whether they are large philosophical questions like “Why is the sky blue?” or something as simple as “Why do onions make me cry?” – these questions can be answered with chemistry. Keep reading to find out how!

1. Why Is the Sky Blue?

You may be aware that the light that comes from the sun is termed “white light”. This kind of light actually contains all the colours of the spectrum, all of which can be seen after a rainstorm in the form of a rainbow. Cool right?

On a nice day when the sun is high in the sky, the gas particles in the air absorb only the short wavelengths of light and results in the reflection of blue light in all directions. If you look closely you may notice that the blue colour of the sky seems to fade as it reaches the horizon.

This is because the light has to travel a much longer distance to reach our eyes and some of the blue light waves are scattered away. This also explains the phenomenon we sometimes see at sunset with a plethora of colours in the sky. Dust and particles in the atmosphere absorb different wavelengths of light, sending colours of pink, purple, and orange to our eyes.

2. Crying While Cutting Onions? It’s Actually Sulphuric Acid!

Now, let’s address the irritating question. Why do we cry when cutting onions? Many of us have experienced the irritating – and sometimes painful – phenomenon associate with cutting onions. But how can chemistry explain this?

The act of cutting or damaging the onion produces a chemical known as thiopropanol S-oxide. This chemical wafts upwards towards the eyes and upon landing on the cornea, stimulates a nervous response from the tear glands. The water that rushes towards the irritant, or the “tears”, is an effort to dilute and neutralize the thiopropanol S-oxide. However, the water actually reacts with thiopropanol S-oxide and creates sulphuric acid, which explains the burning sensation we get along with the tears and the need to create more tears to continue to attempt to flush it away.

Chemistry also explains why we stop crying once we put the onions in the pan and cook them. This heat inactivates the enzymes so they no longer create the toxic reaction on the surface of our eyes. The kitchen has a lot of examples of chemistry, what else can you think of?

3. Brain Chemistry

Those are just two of an endless number of cool science experiments going on all around us. Speaking of crying, what about our real emotions? Did you know that feelings of sadness and happiness (and all the other emotions!) can be explained by chemistry?

Our brains contain many chemicals that can dictate our emotions like dopamine, norepinephrine, and serotonin. Dopamine, also known as the “pleasure chemical”, hangs out in the neurons of our brain. When something good happens to us, dopamine travels through the synapse between two neurons and attaches to receptors on the neighbouring neuron.

This interaction occurs thousands of times, sending dopamine through a network of neurons in the brain and giving us the feeling of pleasure. It’s the result of imbalances in chemicals like dopamine or even faulty synapse interactions that result in depression and other mental or emotional disorders. Interesting, right?

4. How Does Soap Work?

Now, back to the kitchen. Soap? The molecules in soap are polar, one end is hydrophobic and the other extremely hydrophilic. In dirty dishes, multiple soap molecules surround oil or grease molecules in order to wash them away. The hydrophobic end is bonded to the oil while the hydrophilic end bonds easily with water. This allows the oil or grease on your dishes to be surrounded by the soap molecules and washed away easily down the drain. Think about it next time you wash dishes, it might make the task a little more interesting!

Chemistry Is Everywhere!

These are just a few ways that chemistry is found throughout our lives. So next time you’re listening to an A Level Chemistry tutor or lecturer consider how the topic might affect your life. It’s easy to focus solely on memorizing or learning as much as possible but if you’re interested and invested in the topic, it makes it that much easier to learn.

We hope that this article has ignited excitement for all things chemistry, and we hope that these examples stick with you through your studies. We also hope it inspires you to seek out more examples and look closer at the products around you and how chemistry affects all our lives.

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7 Real-Life Frankenstein Experiments Carried Out By Mad Scientists Throughout History

In 1818, mary shelley published her classic novel about dr. frankenstein and his disturbing experiments with reanimation — but the stories of these seven scientists from history prove that reality can sometimes be stranger than fiction..

Wikimedia Commons Dr. Frankenstein at work in his lab, from the seventh page of Mary Shelley’s Frankenstein; or, The Modern Prometheus .

In 1818, a 20-year-old woman named Mary Shelley anonymously published her first novel. Titled Frankenstein; or, The Modern Prometheus , the book told the story of the proverbial mad scientist who reanimated a corpse and created a now-famous monster.

Though Shelley carefully omitted any exposition in her book of how, exactly, Dr. Frankenstein brought his cadaver back to life, modern interpretations of the novel almost always have a lightning bolt zapping the creature into existence. This now-cliché tableau may not be exactly what Shelley had in mind when she wrote the story, but surprisingly, it was not far off from how contemporary scientists had been attempting similar experiments.

For decades before and after the book’s publication, several prominent scientists were putting serious brainpower into the job of reanimating corpses in their own real Frankenstein experiments.

Luigi Galvani, The Italian Biologist Interested In ‘Medical Electricity’

Wikimedia Commons Italian physicist and biologist Luigi Galvani developed an interest in “medical electricity” and how it could be used on animals.

Bringing dead things to life with the power of electricity was an old idea even when Shelley started writing in 1818. Decades before, in 1780, Italian scientist Luigi Galvani noticed an effect that would set him on the path to performing the sort of grisly experiments that could have inspired Frankenstein .

Galvani was a lecturer at the University of Bologna. Scientists of the late 18th century weren’t necessarily specialists, and so Galvani was interested in everything. He was a chemist, physicist, anatomist, physician, and philosopher — and he seemingly excelled in each field.

In the late 1770s, after nearly 20 years of studying obstetrics, comparative anatomy, and physiology, Galvani turned his attention to frogs’ legs. According to the legend that later developed around his work, Galvani was skinning the severed lower half of a frog when his assistant’s scalpel touched a bronze hook in the animal’s flesh. All at once, the leg twitched as if it were trying to hop away.

The incident gave Galvani an idea — and he started experimenting.

He published his results in 1780. Galvani hypothesized that the muscles of dead frogs contained some vital fluid he called “animal electricity.” This, he argued, was related to — but fundamentally distinct from — the kind of electricity in lightning or the static shock that can come after walking across carpet.

He believed the electrical contact animated whatever residual animal-electric fluid remained in the frogs’ legs. This sparked a respectful argument with Alessandro Volta, who confirmed Galvani’s experimental results but disagreed that there was anything special about animals and their electricity.

A shock was a shock, he argued — and then he invented an electric battery to prove it. By 1782, Volta was shocking all sorts of dead things himself to prove any old electricity could do the trick.

Meanwhile, Galvani’s name was cemented in scientific history as the inspiration for the term “galvanism,” or electricity produced by a chemical action.

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8 Fun Science Experiments You Can Easily do at Home

Looking for a science project to do with kids these experiments go beyond the trivial and incorporate real-world scientific research..

Citizen Science Salon is a partnership between  Discover  and  SciStarter.org .

Around the world, millions of kids are headed back to school in a totally different way. Classes are online. Teachers talk to students in virtual classrooms. And parents are often left looking for new, hands-on science learning opportunities.

We’ve got your back. Here are eight fun and easy science experiments that you can do at home with kids of all ages. What’s more, each of these science projects ties into real-life research efforts through citizen science , where volunteers help experts collect and analyze data. 

Make Wild Sourdough

It seems like the whole world is baking homemade sourdough bread right now. Sourdough took on broad appeal when the baker’s yeast disappeared from store shelves. Unlike other baking projects, sourdough doesn’t need store bought yeast. Instead, it’s made with sourdough starter. 

If you have flour, you can easily experiment with making your own sourdough starter. Wild sourdough starters tap into the abundant yeast in our homes and puts them to work making delicious bread. When it comes to science experiments you can do at home, few could be more delicious and rewarding than this one. You’ll also be helping scientists out along the way.

The Wild Sourdough Project is a global science experiment that hopes to discover how sourdough starter communities form over time. The team behind the effort is hoping to unravel how factors like geography and different kinds of flour affect the yeast communities. Best of all, the effort has a step-by-step guide that lets you learn how to make your own sourdough starter. 

Take Part: Make Your Own Sourdough for Science

Create a Cloud in a Jar 

Clouds are an important and often overlooked driver of Earth’s temperature. They trap sunlight in, but they also reflect it back into space. That role has climate scientists rushing to study our planet’s clouds, and how they’re changing. NASA’s GLOBE Observer: Clouds project taps citizen scientists to provide pictures of the sky, plus observations of cloud cover, type, sky conditions and visibility. That data helps info real science research and verify what satellites are seeing from space.

You can get involved with your kids and enrich the experience by adding lessons about clouds. For example, NASA has added a number of fun and easy ways to learn about climate science and clouds, including science experiments. One of the best related projects is to make a cloud in a jar . This simple science experiment is a powerful way to demonstrate how clouds work. You only need water, ice, a jar, and a few minutes of time. 

Take Part: Join NASA's Globe Observer: Clouds

Measure Rain and Snow with CoCoRaHS 

Fall is approaching fast, which means many of us will soon be at home watching rain and snow out the window. Instead of succumbing to the gloom, why not make that weather into a fun science experiment for your kids? 

The CoCoRaHS weather monitoring program , or Community Collaborative Rain, Hail, and Snow Network, is a network of volunteers who measure and report on precipitation. CoCoRaHS emphasizes training and education, and they even have an interactive website rich in educational resources and even National Weather Service lesson plans you can use at home. 

As a volunteer, you’ll use the same low-cost weather gauges that meteorologists and cities use. Then, when it rains, snows or hails, you’ll submit your precipitation data to the website where you can compare it to others in real-time. That information also helps out the National Weather Service, as well as researchers, farmers, emergency managers — and curious people everywhere. 

Take Part: Join the CoCoRaHS Weather Monitoring Network

Plant a Pollinator Garden

Pollinators play a vital role in Earth’s ecosystems, and yet they’re threatened by pesticides, disease, habitat loss and even climate change. That has many people searching for ways to help save bees and other pollinators . 

There are many options to chip in, but one of the most impactful things you and your kids can do at home is plant a pollinator garden. 

Not only will this serve to help struggling pollinators, it can also serve as a long-term science laboratory at home. SciStarter, the citizen-science group behind this blog post, has compiled an entire group of at-home science projects that can be done from your pollinator garden . You can watch moths, butterflies, bees, hummingbirds and more, then help scientists track their migration across the country. 

Take Part: Plant a Pollinator Garden

Build a Bee Condo

If you already have a bumper garden at home, or it’s getting too cold to think about planting just yet, you can still stay indoors and help pollinators. The group behind National Pollinator Week has put together instructions for how you can build a home for native bees, called a bee condo. Unlike domesticated honey bees that live in apiaries, most native, wild bees you find in your backyard actually burrow their homes into the soil or a tree. 

By building a bee condo , you can encourage bees to live nearby and also get a fun, DIY science experiment to do at home. Once it’s up, you can watch what kinds of critters take up residence there and report back on the results for science. 

Take Part: Build a Bee Condo

Scan the Night Sky

Around the world, light pollution from buildings and street lamps is blocking our view of the night sky. Most people who live in cities have never seen a truly dark sky, or the Milky Way. That’s not just bad for humans, it’s also bad for the plants, animals and insects who are disrupted by light pollution. 

If you have a budding astronomy-lover in the house, you can participate in a science project called Globe at Night that aims to create a world-wide measure of light pollution in our night sky. 

For this science experiment, you can start making observations using only a smartphone. You’ll mark the sky’s darkness by how many stars you can see. And you can get a sky quality meter through the project to help record even better data.

Take Part: Measure Light Pollution in Your Community

Measure Water Quality

More than 1.5 million volunteers from across the planet are already taking part in a science experiment to track — and protect — Earth’s waterways. The citizen science effort is called the EarthEcho Water Challenge , and it has users buy a water test kit for about $25, then start collecting basic water data. 

Volunteers record things like water clarity, temperature, pH and dissolved oxygen. That data gets plugged into a large database, where it’s used for real science research and to help protect waterways. 

Take Part: Join the Earth Echo Water Challenge

Study the Vitamin C in Your Juice

Back in the golden age of sailing, sailors worried that they’d get scurvy. A lack of vitamin C during long voyages can cause a host of health problems. Scurvy leaves you weak, causes skin problems and gum disease, and makes it harder to heal. Scurvy can even kill you. This isn’t just an old-timey concern, either. Future space explorers will have to worry about vitamin C as they head off to explore the solar system. And that’s the angle utilized by a fun citizen science project called Space Scurvy . 

The project asks students to use household items to test the vitamin C content of juices from their schools and homes. The necessary tools for this science experiment should be easy to come by, and the site has fun and simple directions for you to follow.

Take Part: Measure Vitamin C for the Space Scurvy Project

Note: Some of these projects are SciStarter Affiliates. You can use your SciStarter account email to join and earn credit for your participation in your SciStarter dashboard.

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An experiment for consciousness scientists and philosophers across three countries debate it.

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What is the fundamental nature of consciousness

Last year, scientists inferentially detected the existence of mental objects that fundamentally change vision science. “The question becomes, what are they exactly? Are they patterns of neurons firing? Are they some kind of phenomenon not necessarily reducible to any kind of physical substrate?” Asks Jessica M. Wilson, philosopher and author of the book Metaphysical Emergence .

Coming up, scientists and philosophers spanning three countries weigh in on an experiment to discover the material nature of consciousness and the content of our experiences.

Let’s start with a definition. Broadly speaking, consciousness is awareness. It’s the qualitative experience of that awareness—what it’s like to be something.

The Philosophers

Wilson, like many of her peers, doesn’t see anything controversial about the idea that mental representations might be actual things that exist in space and time and populate conscious experience. Sensory information and neurons firing seem to be involved in our vibrant, dynamic mind show.

But there’s little consensus about how activity at the level of our neurons turns into conscious experience. This is The Hard Problem of Consciousness, a term defined by philosopher and cognitive scientist David Chalmers. How does microscopic activity in your brain turn into the large, rich experience of sitting on a shoreline watching a kaleidoscopic halo over the rising sun? While The Easy Problem is how the brain works, The Hard Problem is how brain workings turn into experience.

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Theories about the fundamental nature of consciousness fall roughly into two camps: The first camp, called Identity Theory , thinks conscious experiences are identical to neural events. Mark Balaguer, philosopher, identity theorist, and author of the book Free Will , thinks conscious events are identical to neural events the same way Clark Kent is identical to Superman. It may seem to Lois like they’re not identical. For instance, Lois doesn’t think Clark can fly. When Lois looks at him, “he doesn't seem to be a flyer,” says Balaguer. “But my view is that he actually is a flyer." For Balaguer, if you don’t think they’re identical, you’re committed to a “spooky dualist view” — meaning you believe consciousness is something like a soul.

The second camp views conscious experience as something that isn’t identical to neural events. This is because experience has qualia, i.e. “what it feels like,” whereas neural events don’t have this property. For the second camp, consciousness emerges from complex systems like brain activity, and it can emerge in two ways. “ Weak Emergence describes new properties arising in systems as a result of the interactions at an elemental level,” says Wilson, describing a theory where a conscious event emerges as a new thing that can be reduced to the sum of its parts. Strong Emergence is the theory that consciousness emerges as something entirely different than the sum of its parts.

An Experiment For Strong Emergence

Most theories of strong emergence are dualistic. Dualism is the view that there’s a natural, physical world that can be explained by science versus a spiritual world that can’t. For dualists, conscious experience exists in the realm of the spiritual world. But the theory that consciousness emerges as something entirely new doesn’t necessarily require a break from natural laws. Science evolves by trying to fit new observations into an already established framework. If new observations can't be explained by the prevailing scientific theory, a hypothesis is proposed and tested. Depending on the results, the old scientific theory is amended or a new one is created.

An example of this in action is the First Law of Thermodynamics— Conservation—which states that energy can’t be created or destroyed. It’s always conserved. But when physicists observed something that looked like it was breaking this law, they proposed a new particle called the ‘neutrino’ and a new force called the ‘weak force’ or ‘weak interaction.’ This was a fundamental, irreducible new force. The hypothesis was demonstrated experimentally and a new fundamental interaction was incorporated into our explanation of the natural world.

Wilson considers it scientifically respectable to say that consciousness might be a new, fundamental interaction that emerges at a certain level of system complexity, which would be Strong Emergence. However, Wilson cautions that the theory has yet to be substantiated.

Taking the weak nuclear interaction as a model, Wilson thinks the hypothesis of strongly emergent consciousness might be something we can test for, at least in principle. The first step would be to come up with a hypothesis based on the known fundamental physical interactions, predicting the overall energy of a complex system, like an octopus brain. The next step would be to test for any apparent violations in the conservation of energy of this system. If a violation is observed, this might point to strong emergence, just as the apparent violation of conservation of energy led to the discovery of a new interaction.

The Scientists Respond — Specifically, A Physicist, An Anesthesiologist, A Cognitive Neuroscientist And A Developmental And Synthetic Biologist

“It’s pseudoscience,” says Eric Carlson, associate professor of physics at Wake Forest University about Wilson’s proposition to test for Strong Emergence. “We know very well that consciousness is the action of the brain, which operates on electrochemical principles.” Carlson says testing to see if consciousness is a new interaction legitimizes junk science. “There were spiritualists who tried to demonstrate the existence of souls through physical manifestations. And some people thought it had to do with electromagnetic radiation or something. And we still have ghost hunters walking around measuring electromagnetic fields." For Carlson, Strong Emergence is a vintage, debunked investigation into the existence of a soul, repackaged as “consciousness theory.”

Carlson admits he’s not caught up on the growing body of evidence that organisms without neurons (like plants and slime molds ) are capable of memory, thinking, problem-solving and learning—or that it’s getting harder for researchers to explain away these behaviors as purely nonconscious and mechanical. Consciousness in brainless organisms undermines the claim that consciousness is an action of the brain. While the brain is undoubtedly involved in human and animal consciousness, if beings without brains can be conscious, then what consciousness is must have another explanation.

“I don't know how you test for [ Strong Emergence ]. I don't think consciousness is in essence, an emergent property, which means that it emerges at a higher level of complexity,” says Stuart Hameroff, anesthesiologist and professor at University of Arizona. “Actually, I think it's a basic fundamental property of the universe. Every time there's a collapse, there's a little blip of experience.”

Hameroff is the co-author of a theory of consciousness with Nobel Prize-winning physicist, Sir Roger Penrose. Their theory is Orchestrated Objective Reduction or the Orch OR Theory of Consciousness — the theory that consciousness arises from quantum wave function collapses inside microtubules. It’s a polarizing theory and one of the few theories of consciousness that has the potential to be tested and either proved out or falsified.

What’s a quantum wave function collapse? “Einstein demonstrated with his theory of general relativity that large objects cause big curvatures in spacetime,” says Hameroff. “Penrose applied this on a microscale saying tiny particles cause tiny curvatures in spacetime. A single particle in quantum superposition of two locations would have opposing curvatures, a separation in the structure of spacetime. These separations are unstable, and self-collapse, causing consciousness. That is the origin of qualia and phenomenal experience.”

According to Orch OR, quantum collapses that give over to proto-conscious moments are happening everywhere in the universe. This is not consciousness. These moments of proto-consciousness are the building blocks for consciousness. The blocks get assembled in an orchestrated way inside microtubules. Microtubules are fractal structures inside cells. They can be found in plants, unicellular organisms, and inside neurons. They help cells keep their shape and internal order. Although smaller than a neuron, microtubules may be large enough to host proto-conscious events–quantum collapses—of a particular scale or quantity necessary to give rise to conscious experience.

“I think the basic problem is the brain is not strictly a computer. It's more like an orchestra. It's a multi-scale hierarchy that goes downward, inside neurons, to the microtubules and then to the quantum level,” says Hameroff, who likens proto-consciousness to the atonal notes when musicians in an orchestra tune their instruments. Once the performance begins, the notes harmonize. If proto-conscious events are like individual notes, and microtubules the orchestra, then consciousness is the symphony. Until quantum collapses become organized by microtubules into conscious experience, Hameroff thinks these random, disconnected proto-conscious moments occur everywhere. “They’re the origins of life. Or they prompted the origins of life. They're driving evolution.”

Tests for quantum collapse due to spacetime separation are currently underway in multiple labs, like The Bouwmeester Lab—run by Dirk Bouwmeester’s team—at University of California, Santa Barbara and Ivette Fuentes’s research group at University of Southampton. Results from these experiments might resolve the measurement problem in quantum mechanics, a big problem for physics and a big part of the Orch OR theory. However, these experiments are not designed to show that quantum collapse produces proto-consciousness.

Orch OR also needs to show that cognition depends on microtubule activity, which Anirban Bandyopadhyay, a senior scientist at the National Institute for Materials Science (NIMS) in Tsukuba, Japan was able to demonstrate. Bandyopadhyay’s research also shows the presence of quantum effects in microtubules. But the microtubule activity linked to cognition has yet to be shown to be quantum.

Another critical test in proving Orch OR is the actual manipulation of consciousness, turning consciousness on and off through anesthesia.

“General anesthesia basically affects consciousness and very little else in the body,” says Hameroff, who points out that the brain is still active under anesthesia even though you are not conscious. Anesthesia seems to target consciousness. And anesthetic gases work by a quantum interaction. “We have shown quantum effects in microtubules and are attempting to prove their relevance to consciousness by testing for sensitivity to anesthetics proportional to anesthetic potency,” says Hameroff. “We should know within a year.”

Why Does Science Need To Solve The Problem Of Consciousness?

“Figuring out how we go from a neural event to a psychological experience, that's absolutely fundamental,” says Jacob Bellmund, a cognitive neuroscientist at the Max Planck Institute for Human Cognitive and Brain Sciences in Germany. While Bellmund’s research doesn’t focus on what consciousness is, he looks at the neural substrates that produce mental representations. Specifically, Bellmund works in the area of memory and cognitive representations of space and time.

His previous research looked at grid and place cells inside the brain that function as our internal GPS, navigating us through the world. Bellmund and a team of researchers from around the world discovered that these cells produce a trajectory through cognitive space, a coordinate system for our thoughts where we collect and piece together properties of a concept. “Our train of thought can be considered a path through the spaces of our thoughts, along different mental dimensions.” Bellmund’s findings served as the basis for the hypothesis that knowledge is organized spatially in the mind. “I'm currently working on temporal memories,” says Bellmund. “How we remember when things happened, how we build this representation.”

As with all cognitive neuroscientists straddling neuroscience and psychology, Bellmund has to resort to abstract terms like cognitive spaces and mental dimensions to describe experiences. When it comes to the relationship between neural activity and cognition, “I think it's important to understand how this arises,” says Bellmund. He doesn’t think it’s accurate to say that neural events are identical to cognitive events, though he doesn’t know how to design an experiment to settle this question.

"You can't just have opinions on this,” says Michael Levin, a developmental and synthetic biologist at Tufts University conducting intelligence studies on slime molds. “You have to do experiments.” Levin insists scientists need to propose various definitions of consciousness, examine which definition gives a better understanding of a conscious system, and then do experiments to predict and control conscious systems. Levin thinks consciousness arises on a continuum, with a sort of higher degree of fidelity the more complex the system. “If evolution is true, then these cognitive capacities appear somewhere, and if you think it's binary, you can't just say it, you have to propose an empirical explanation of what is different and where the jump happens.”

Levin also sees an inherent problem in trying to use an objective discipline like the scientific method to make sense of subjective experience. “You can communicate predictions of stories about brains and about cognition and about computation,” he says. “Let's say you have a perfect, correct theory of consciousness. Okay. What format are your predictions in?”

For every other scientific theory, there’s an objective third-person story about what’s going on. For cognitive neuroscience, it’s third-person observations and descriptions of neuronal and human behavior.

Levin’s not sure how to objectively observe and communicate findings about consciousness. “How could you possibly know if you have a correct theory of consciousness if you can't even tell me what shape the answers are going to be in, what language are they going to be in? I don't think there is a third-person story to be told about consciousness.”

Why Does Humanity Need To Solve The Problem Of Consciousness?

Technically, we don’t. We can continue to live with the ironic fact about our existence: That there’s nothing we know better, more directly and more intimately than our consciousness. And there’s virtually nothing in the universe that remains a bigger mystery. Meanwhile, the need to bridge that gap and understand consciousness might be a clue to solving it. But that’s another—upcoming—story: Testing A Time-Jumping, Multiverse-Killing, Consciousness-Spawning Theory Of Reality

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• 14 August 2024

What is the hottest temperature humans can survive? These labs are redefining the limit

• Carissa Wong

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Dousing the skin and clothes with water is one cost-effective way to protect the body from overheating. Credit: Rehman Asad/NurPhoto/Getty

This story is part of special report on science and extreme heat. Read about the effects that extreme heat has on the body , how climate change is intensifying health problems and the record-breaking warming at the Great Barrier Reef .

In 2019, physiologist Ollie Jay started designing a chamber that could simulate the heatwaves of today and of the future. Eighteen months later, the Aus$2-million (US$1.3-million) structure was built, packed up in Brisbane, Australia, and driven 1,000 kilometres to the University of Sydney, where it was lifted to the top floor of a shiny glass building. Now, researchers including Jay are using it to test the limits of human survival in extreme heat , which are surprisingly poorly understood.

Cities must protect people from extreme heat

“The trouble is that, today, you have these conditions that can sound hot, but we don’t really know what it’s going to do to people,” says Jay, who directs the heat and health laboratory at the University of Sydney. “By simulating those conditions and exposing people to them, under careful medical supervision, we can better understand the physiology of how people will respond,” he says. Jay’s team is also exploring which cooling strategies work best to reduce the health risks of heat exposure.

As climate change heats Earth, blistering days have become a regular feature of weather reports worldwide. Last month, the record for the world’s hottest day was broken twice, and the United Nations made a global call for action on extreme heat, to help vulnerable people, workers and economies to cope using science. Around 70% of the global workforce — 2.4 billion people — are now at high risk of extreme heat, it said.

Despite this, public advice on how to cope with high temperatures is poor, and ways that people can effectively cool themselves have not been well studied. “If you look at heat advisories from well-respected organizations like the US Centres for Disease Control and Prevention, the World Health Organization, they’re fraught with errors when it comes to human physiology,” says Larry Kenney, a physiologist at Pennsylvania State University in University Park.

Researchers at the University of Sydney monitor how heat is affecting a pregnant woman in their climate chamber. Credit: University of Sydney/Stefanie Zingsheim

Chamber of heat

Jay’s team is using its state-of-the-art climate chamber to investigate the conditions under which heat threatens life, how, and what practical, evidence-based ways there are to stay cool.

The chamber is a room 4 metres by 5 metres. Researchers can dial the temperature up or down by 1 °C every minute — from 5 °C to a searing 55 °C — control windspeed and simulate sunlight using infrared lamps. They can also fine-tune humidity, a key variable that influences heat’s effects on the body. “It’s quite the engineering feat,” says Jay.

Extreme heat harms health — what is the human body’s limit?

Trial participants can eat, sleep and exercise inside the chamber; researchers pass food and other items to them through a hatch. Sensors attached to them send information to the adjacent control room, which processes data on variables including heart rate, breathing, sweating and body temperature.

Heat thresholds for humans have been poorly defined in part because public-health bodies have over-relied on a theoretical study published 1 in 2010, says Jay. In that paper, researchers used mathematical models to define the ‘wet-bulb temperature’ (WBT) at which a young, healthy person would die after six hours. WBT is a measure that scientists use when studying heat stress because it accounts for the effects of heat and humidity.

The models churned out a WBT of 35 °C as the limit of human survival. At that threshold, the body’s core temperature would rise uncontrollably. But the model treated the human body as an unclothed object that doesn’t sweat or move, making the result less applicable to the real world.

Ollie Jay’s lab is studying how heat affects people who are exercising to mimic everyday activities. Credit: University of Sydney/Stefanie Zingsheim

Despite this, countless public-health bodies adopted it — even the Intergovernmental Panel on Climate Change — reducing the motivation to obtain a more relevant number, says Jay. “It’s a basic physical model with many limitations — but nearly everyone’s using this.”

Lowered limit

In a 2021 study, Kenney and his colleagues provided a better estimate: a WBT survival limit of around 31 °C. They calculated it by tracking the core body temperature of young, healthy people under different combinations of temperature and humidity while they were cycling 2 .

“You do still see the 35 °C wet-bulb temperature tossed around, but people are starting to come around to the limit defined by Kenney’s lab,” says Robert Meade, a heat and health researcher at Harvard University in Cambridge, Massachusetts.

Kenney’s group also works with a climate chamber, and there are dozens worldwide, many dedicated to sports science. But Kenney says that just a few groups, including Jay’s, are at the forefront of using them to better understand how people cope in extreme heat.

Physiological model

Jay’s team is now testing a mathematical model of how the body copes in extreme heat, which it published 3 last year. The model uses data from studies that have measured sweating capacity in older and younger people, and it follows physical laws to predict how heat is transferred between the body and environment.

“The fact that they incorporated physiology, which very few models do, and do well — I think this makes it the best model right now out there,” says Kenney, who has collaborated with Jay on other research.

Most models of the body’s response to heat focus on young, healthy people in the shade. But Jay and his team’s model estimated the limits of survival in the shade and sunlight across ages and while people were resting or exercising. Among their results, they estimated WBT survival limits of between 26 °C and 34 °C for young people and 21 °C to 34 °C for older people.

“The flexibility and the ability to very easily assess these different scenarios is the key advance of the model,” says Meade.

Workers in a garment factory in Bangladesh, where long hours and hot weather can affect employees’ health. Credit: Kazi Salahuddin Razu/NurPhoto/Getty

Unsurprisingly, the model suggests that survival limits are lower when people are exposed to the Sun versus in the shade, and for people over 65 years old compared with those aged 18–40. The team also used the model to define livability limits — conditions in which older and younger people could safely carry out tasks such as desk-work, walking, climbing stairs, dancing and heavy lifting. Despite its strengths, the model still needs to be tested further in people, says Meade.

To do this, Jay’s team is first exposing young, healthy people in the climate chamber to combinations of temperature and humidity while monitoring variables such as their core body temperature, heart rate and sweating up to a temperature threshold above which it would be unsafe.

Read the paper: Extreme escalation of heat failure rates in ectotherms with global warming

In future trials, the researchers plan to test the body’s response to heat in shady and sunlit conditions, across ages and during exercise. They will use data from these trials to improve the model, which, in turn, can be used to develop better health advice for people most at risk in high heat.

Need to chill

The lab’s other focus — finding effective cooling strategies — involves mimicking the conditions of environments where heat can affect workers’ health. In one trial, Jay’s team is testing cooling strategies that could help garment-factory workers in Bangladesh, where people typically work long hours in hot climates, with little access to air conditioning.

The researchers previously measured the heat and humidity across three floors of a clothing factory in the capital, Dhaka. “We recreated those conditions in the chamber, and the work that people did — the women did sewing and the men did ironing,” he says. The trial participants wore clothing that workers would typically wear in the factory.

Participants in Jay’s lab have recreated the conditions of a garment factory in their climate chamber to investigate effective cooling methods. Credit: University of Sydney/Stefanie Zingsheim

Across some 240 climate-chamber trials, the team measured people’s body functions and their work productivity, says Jay, “because one of the problems is that people slow down when they get hot”. The scientists tested cooling methods such as using fans and regularly drinking water, and simulated the effects of changing the colour of the factory roof. The researchers plan to submit their results to a journal.

Jay’s team has also explored how electric fans and skin-wetting affect heart strain in older people, across different combinations of heat and humidity. The researchers found that, in humid conditions, fan use reduced heart strain up to an air temperature of at least 38 ˚C. But in dry heat, fan use increased heart strain. Wetting the skin was beneficial in both dry and humid heat.

“Identifying the situations in which common cooling strategies, such as fan use and dousing the skin with water, work best is essential to protect public health,” says Meade.

Low-tech cooling

Jay and his colleagues have already popularized a method for cooling babies in prams. “On a hot day, people are covering their baby strollers with these white muslin cloths — but there’s all this contention as to whether it’s a good or bad thing,” he says. In a 2023 study 4 , the team found that a dry, white muslin cloth can heat up prams by more than 2.5 °C, but a damp one had the best cooling effect. “It extracts the latent heat energy from inside the pram and keeps it cooler by about 5 °C,” he says.

A man is treated for heatstroke in Varanasi, India, which has been experiencing periods of severe heat since May.

The study drew media attention. “What was pretty cool is, two weeks later, I’m walking around where I live and I start seeing parents pushing along their white muslin cloths with a spray bottle,” he says.

The team has also helped to shape a global heat-alert system released by the Google Chrome browser for its users worldwide. “If it knows where you are, and the heat exceeds a certain threshold, then you get an extreme-heat warning,” he says. The alert provides cooling tips such as to drink one cup of water per hour and to wet skin and clothing.

Next year, Jay’s lab will track how heat affects birth outcomes and maternal health in pregnant women in Bangladesh. He’s seeking funding to conduct a randomized controlled trial of cooling strategies in India during the hot season.

Jay’s ultimate goal is to protect people’s health in a world that’s becoming ever more hostile. “When I first came over to Sydney, I basically took a big demotion — there was an old chamber that wasn’t really working well, and I had about Aus$16,500 of start-up funding,” says Jay. “We have been lucky and fortunate to be able to bring in some good funding, and make some good traction in this area.”

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Top 5 physics experiments you can do at home

October 17, 2022 By Emma Vanstone Leave a Comment

Physics is key to understanding the world around us. While some aspects may seem tricky to understand, many fundamental physics concepts can be broken down into simple concepts, some of which can be demonstrated using basic equipment at home.

This list of 5 physics experiments you can try at home is a great starting point for understanding physics and, hopefully a source of inspiration for little scientists everywhere!

Physics experiments you can do at home

1. archimedes and density.

The story behind Archimedes’ discovery of density is that he was asked by the King of Sicily to work out whether a goldsmith had replaced some gold from a crown with silver. Archimedes needed to determine if the goldsmith had cheated without damaging the crown.

The crown weighed the same as the gold the King had given the goldsmith, but gold is more dense than silver, so if there were silver in the crown its density would be less than if it were pure gold. Archimedes realised that if he could measure the crown’s volume, he could work out its density, but calculating the volume of a crown shape was a tough challenge. According to the story, Archimedes was having a bath one day when he realised the water level rose as he lowered himself into the bathtub. He realised that the volume of water displaced was equal to the volume of his body in the water.

Archimedes placed the crown in water to work out its density and realised the goldsmith had cheated the king!

Density Experiment

One fun way to demonstrate density is to make a density column. Choose a selection of liquids and place them in density order, from the most dense to the least dense. Carefully pour a small amount of each into a tall jar or glass, starting with the most dense. You should end up with a colourful stack of liquids!

2. Split light into the colours of the rainbow

Isaac Newton experimented with prisms and realised that light is made up of different colours ( the colours of the rainbow ). Newton made this discovery in the 1660s. It wasn’t until the 1900s that physicists discovered the electromagnetic spectrum , which includes light waves we can’t see, such as microwaves, x-ray waves, infrared and gamma rays.

How to split light

Splitting white light into the colours of the rainbow sounds tricky, but all you need is a prism. A prism is a transparent block shaped so light bends ( refracts ) as it passes through. Some colours bend more than others, so the whole spectrum of colours can be seen.

If you don’t have a prism, you can also use a garden hose! Stand with your back to the sun, and you’ll see a rainbow in the water! This is because drops of water act like a prism.

3. Speed of Falling Objects

Galileo’s falling objects.

Aristotle thought that heavy objects fell faster than lighter objects, a theory later disproved by Galileo .

It is said that Galileo dropped two cannonballs with different weights from the leaning tower of Pisa, which hit the ground at the same time. All objects accelerate at the same rate as they fall.

If you drop a feather and a hammer from the same height, the hammer will hit the ground first, but this is because of air resistance!

If a hammer and feather are dropped somewhere with no air resistance, they hit the ground simultaneously. Commander David Scott proved this was true on the Apollo 15 moonwalk!

Hammer and Feather Experiment on the Moon

Brian Cox also proved Galileo’s theory to be correct by doing the same experiment in a vacuum!

While you won’t be able to replicate a hammer or heavy ball and feather falling, you can investigate with two objects of the same size but different weights. This means the air resistance is the same for both objects, so the only difference is the weight.

Take two empty water bottles of the same size. Fill one to the top with water and leave the other empty. Drop them from the same height. Both will hit the ground at the same time!

4. Newton’s Laws of Motion

Sir Isaac Newton pops up a lot in any physics book as he came up with many of the laws that describe our universe and is undoubtedly one of the most famous scientists of all time. Newton’s Laws of Motion describe how things move and the relationship between a moving object and the forces acting on it.

Making and launching a mini rocket is a great way to learn about Newton’s Laws of Motion .

The rocket remains motionless unless a force acts on it ( Newton’s First Law ).

The acceleration of the rocket is affected by its mass. If you increase the mass of the rocket, its acceleration will be less than if it had less mass ( Newton’s Second Law ).

The equal and opposite reaction from the gas forcing the cork downwards propels the rocket upwards ( Newton’s Third Law ).

4. Pressure

Pressure is the force per unit area.

Imagine standing on a Lego brick. If you stand on a large brick, it will probably hurt. If you stand on a smaller brick with the same force it will hurt more as the pressure is greater!

Snowshoes are usually very wide. This is to reduce the pressure on the snow so it sinks less as people walk on it.

Pressure and Eggs

If you stand on one egg, it will most likely break. If you stand on lots of eggs with the same force, you increase the area the force is applied over and, therefore, reduce the pressure on each individual egg.

That’s five easy physics experiments you can do at home! Can you think of any more?

Last Updated on June 14, 2024 by Emma Vanstone

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7 Famous Psychology Experiments

Many famous experiments studying human behavior have impacted our fundamental understanding of psychology. Though some could not be repeated today due to breaches in ethical boundaries, that does not diminish the significance of those psychological studies. Some of these important findings include a greater awareness of depression and its symptoms, how people learn behaviors through the process of association and how individuals conform to a group.

Below, we take a look at seven famous psychological experiments that greatly influenced the field of psychology and our understanding of human behavior.

The Little Albert Experiment, 1920

A John’s Hopkins University professor, Dr. John B. Watson, and a graduate student wanted to test a learning process called classical conditioning. Classical conditioning involves learning involuntary or automatic behaviors by association, and Dr. Watson thought it formed the bedrock of human psychology.

A nine-month-old toddler, dubbed “Albert B,” was volunteered for Dr. Watson and Rosalie Rayner ‘s experiment. Albert played with white furry objects, and at first, the toddler displayed joy and affection. Over time, as he played with the objects, Dr. Watson would make a loud noise behind the child’s head to frighten him. After numerous trials, Albert was conditioned to be afraid when he saw white furry objects.

The study proved that humans could be conditioned to enjoy or fear something, which many psychologists believe could explain why people have irrational fears and how they may have developed early in life. This is a great example of experimental study psychology.

Stanford Prison Experiment, 1971

Stanford professor Philip Zimbardo wanted to learn how individuals conformed to societal roles. He wondered, for example, whether the tense relationship between prison guards and inmates in jails had more to do with the personalities of each or the environment.

During Zimbardo’s experiment , 24 male college students were assigned to be either a prisoner or a guard. The prisoners were held in a makeshift prison inside the basement of Stanford’s psychology department. They went through a standard booking process designed to take away their individuality and make them feel anonymous. Guards were given eight-hour shifts and tasked to treat the prisoners just like they would in real life.

Zimbardo found rather quickly that both the guards and prisoners fully adapted to their roles; in fact, he had to shut down the experiment after six days because it became too dangerous. Zimbardo even admitted he began thinking of himself as a police superintendent rather than a psychologist. The study confirmed that people will conform to the social roles they’re expected to play, especially overly stereotyped ones such as prison guards.

“We realized how ordinary people could be readily transformed from the good Dr. Jekyll to the evil Mr. Hyde,” Zimbardo wrote.

The Asch Conformity Study, 1951

Solomon Asch, a Polish-American social psychologist, was determined to see whether an individual would conform to a group’s decision, even if the individual knew it was incorrect. Conformity is defined by the American Psychological Association as the adjustment of a person’s opinions or thoughts so that they fall closer in line with those of other people or the normative standards of a social group or situation.

In his experiment , Asch selected 50 male college students to participate in a “vision test.” Individuals would have to determine which line on a card was longer. However, the individuals at the center of the experiment did not know that the other people taking the test were actors following scripts, and at times selected the wrong answer on purpose. Asch found that, on average over 12 trials, nearly one-third of the naive participants conformed with the incorrect majority, and only 25 percent never conformed to the incorrect majority. In the control group that featured only the participants and no actors, less than one percent of participants ever chose the wrong answer.

Asch’s experiment showed that people will conform to groups to fit in (normative influence) because of the belief that the group was better informed than the individual. This explains why some people change behaviors or beliefs when in a new group or social setting, even when it goes against past behaviors or beliefs.

The Bobo Doll Experiment, 1961, 1963

Stanford University professor Albert Bandura wanted to put the social learning theory into action. Social learning theory suggests that people can acquire new behaviors “through direct experience or by observing the behavior of others.” Using a Bobo doll , which is a blow-up toy in the shape of a life-size bowling pin, Bandura and his team tested whether children witnessing acts of aggression would copy them.

Bandura and two colleagues selected 36 boys and 36 girls between the ages of 3 and 6 from the Stanford University nursery and split them into three groups of 24. One group watched adults behaving aggressively toward the Bobo doll. In some cases, the adult subjects hit the doll with a hammer or threw it in the air. Another group was shown an adult playing with the Bobo doll in a non-aggressive manner, and the last group was not shown a model at all, just the Bobo doll.

After each session, children were taken to a room with toys and studied to see how their play patterns changed. In a room with aggressive toys (a mallet, dart guns, and a Bobo doll) and non-aggressive toys (a tea set, crayons, and plastic farm animals), Bandura and his colleagues observed that children who watched the aggressive adults were more likely to imitate the aggressive responses.

Unexpectedly, Bandura found that female children acted more physically aggressive after watching a male subject and more verbally aggressive after watching a female subject. The results of the study highlight how children learn behaviors from observing others.

The Learned Helplessness Experiment, 1965

Martin Seligman wanted to research a different angle related to Dr. Watson’s study of classical conditioning. In studying conditioning with dogs, Seligman made an astute observation : the subjects, which had already been conditioned to expect a light electric shock if they heard a bell, would sometimes give up after another negative outcome, rather than searching for the positive outcome.

Under normal circumstances, animals will always try to get away from negative outcomes. When Seligman tested his experiment on animals who hadn’t been previously conditioned, the animals attempted to find a positive outcome. Oppositely, the dogs who had been already conditioned to expect a negative response assumed there would be another negative response waiting for them, even in a different situation.

The conditioned dogs’ behavior became known as learned helplessness, the idea that some subjects won’t try to get out of a negative situation because past experiences have forced them to believe they are helpless. The study’s findings shed light on depression and its symptoms in humans.

Is a Psychology Degree Right for You?

Develop you strength in psychology, communication, critical thinking, research, writing, and more.

The Milgram Experiment, 1963

In the wake of the horrific atrocities carried out by Nazi Germany during World War II, Stanley Milgram wanted to test the levels of obedience to authority. The Yale University professor wanted to study if people would obey commands, even when it conflicted with the person’s conscience.

Participants of the condensed study , 40 males between the ages of 20 and 50, were split into learners and teachers. Though it seemed random, actors were always chosen as the learners, and unsuspecting participants were always the teachers. A learner was strapped to a chair with electrodes in one room while the experimenter äóñ another actor äóñ and a teacher went into another.

The teacher and learner went over a list of word pairs that the learner was told to memorize. When the learner incorrectly paired a set of words together, the teacher would shock the learner. The teacher believed the shocks ranged from mild all the way to life-threatening. In reality, the learner, who intentionally made mistakes, was not being shocked.

As the voltage of the shocks increased and the teachers became aware of the believed pain caused by them, some refused to continue the experiment. After prodding by the experimenter, 65 percent resumed. From the study, Milgram devised the agency theory , which suggests that people allow others to direct their actions because they believe the authority figure is qualified and will accept responsibility for the outcomes. Milgram’s findings help explain how people can make decisions against their own conscience, such as when participating in a war or genocide.

The Halo Effect Experiment, 1977

University of Michigan professors Richard Nisbett and Timothy Wilson were interested in following up a study from 50 years earlier on a concept known as the halo effect . In the 1920s, American psychologist Edward Thorndike researched a phenomenon in the U.S. military that showed cognitive bias. This is an error in how we think that affects how we perceive people and make judgements and decisions based on those perceptions.

In 1977, Nisbett and Wilson tested the halo effect using 118 college students (62 males, 56 females). Students were divided into two groups and were asked to evaluate a male Belgian teacher who spoke English with a heavy accent. Participants were shown one of two videotaped interviews with the teacher on a television monitor. The first interview showed the teacher interacting cordially with students, and the second interview showed the teacher behaving inhospitably. The subjects were then asked to rate the teacher’s physical appearance, mannerisms, and accent on an eight-point scale from appealing to irritating.

Nisbett and Wilson found that on physical appearance alone, 70 percent of the subjects rated the teacher as appealing when he was being respectful and irritating when he was cold. When the teacher was rude, 80 percent of the subjects rated his accent as irritating, as compared to nearly 50 percent when he was being kind.

The updated study on the halo effect shows that cognitive bias isn’t exclusive to a military environment. Cognitive bias can get in the way of making the correct decision, whether it’s during a job interview or deciding whether to buy a product that’s been endorsed by a celebrity we admire.

How Experiments Have Impacted Psychology Today

Contemporary psychologists have built on the findings of these studies to better understand human behaviors, mental illnesses, and the link between the mind and body. For their contributions to psychology, Watson, Bandura, Nisbett and Zimbardo were all awarded Gold Medals for Life Achievement from the American Psychological Foundation. Become part of the next generation of influential psychologists with King University’s online bachelor’s in psychology . Take advantage of King University’s flexible online schedule and complete the major coursework of your degree in as little as 16 months. Plus, as a psychology major, King University will prepare you for graduate school with original research on student projects as you pursue your goal of being a psychologist.

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Experimental Method In Psychology

Saul McLeod, PhD

Editor-in-Chief for Simply Psychology

BSc (Hons) Psychology, MRes, PhD, University of Manchester

Saul McLeod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.

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Olivia Guy-Evans, MSc

Associate Editor for Simply Psychology

BSc (Hons) Psychology, MSc Psychology of Education

Olivia Guy-Evans is a writer and associate editor for Simply Psychology. She has previously worked in healthcare and educational sectors.

On This Page:

The experimental method involves the manipulation of variables to establish cause-and-effect relationships. The key features are controlled methods and the random allocation of participants into controlled and experimental groups .

What is an Experiment?

An experiment is an investigation in which a hypothesis is scientifically tested. An independent variable (the cause) is manipulated in an experiment, and the dependent variable (the effect) is measured; any extraneous variables are controlled.

An advantage is that experiments should be objective. The researcher’s views and opinions should not affect a study’s results. This is good as it makes the data more valid  and less biased.

There are three types of experiments you need to know:

1. Lab Experiment

A laboratory experiment in psychology is a research method in which the experimenter manipulates one or more independent variables and measures the effects on the dependent variable under controlled conditions.

A laboratory experiment is conducted under highly controlled conditions (not necessarily a laboratory) where accurate measurements are possible.

The researcher uses a standardized procedure to determine where the experiment will take place, at what time, with which participants, and in what circumstances.

Participants are randomly allocated to each independent variable group.

Examples are Milgram’s experiment on obedience and  Loftus and Palmer’s car crash study .

• Strength : It is easier to replicate (i.e., copy) a laboratory experiment. This is because a standardized procedure is used.
• Strength : They allow for precise control of extraneous and independent variables. This allows a cause-and-effect relationship to be established.
• Limitation : The artificiality of the setting may produce unnatural behavior that does not reflect real life, i.e., low ecological validity. This means it would not be possible to generalize the findings to a real-life setting.
• Limitation : Demand characteristics or experimenter effects may bias the results and become confounding variables .

2. Field Experiment

A field experiment is a research method in psychology that takes place in a natural, real-world setting. It is similar to a laboratory experiment in that the experimenter manipulates one or more independent variables and measures the effects on the dependent variable.

However, in a field experiment, the participants are unaware they are being studied, and the experimenter has less control over the extraneous variables .

Field experiments are often used to study social phenomena, such as altruism, obedience, and persuasion. They are also used to test the effectiveness of interventions in real-world settings, such as educational programs and public health campaigns.

An example is Holfing’s hospital study on obedience .

• Strength : behavior in a field experiment is more likely to reflect real life because of its natural setting, i.e., higher ecological validity than a lab experiment.
• Strength : Demand characteristics are less likely to affect the results, as participants may not know they are being studied. This occurs when the study is covert.
• Limitation : There is less control over extraneous variables that might bias the results. This makes it difficult for another researcher to replicate the study in exactly the same way.

3. Natural Experiment

A natural experiment in psychology is a research method in which the experimenter observes the effects of a naturally occurring event or situation on the dependent variable without manipulating any variables.

Natural experiments are conducted in the day (i.e., real life) environment of the participants, but here, the experimenter has no control over the independent variable as it occurs naturally in real life.

Natural experiments are often used to study psychological phenomena that would be difficult or unethical to study in a laboratory setting, such as the effects of natural disasters, policy changes, or social movements.

For example, Hodges and Tizard’s attachment research (1989) compared the long-term development of children who have been adopted, fostered, or returned to their mothers with a control group of children who had spent all their lives in their biological families.

Here is a fictional example of a natural experiment in psychology:

Researchers might compare academic achievement rates among students born before and after a major policy change that increased funding for education.

In this case, the independent variable is the timing of the policy change, and the dependent variable is academic achievement. The researchers would not be able to manipulate the independent variable, but they could observe its effects on the dependent variable.

• Strength : behavior in a natural experiment is more likely to reflect real life because of its natural setting, i.e., very high ecological validity.
• Strength : Demand characteristics are less likely to affect the results, as participants may not know they are being studied.
• Strength : It can be used in situations in which it would be ethically unacceptable to manipulate the independent variable, e.g., researching stress .
• Limitation : They may be more expensive and time-consuming than lab experiments.
• Limitation : There is no control over extraneous variables that might bias the results. This makes it difficult for another researcher to replicate the study in exactly the same way.

Key Terminology

Ecological validity.

The degree to which an investigation represents real-life experiences.

Experimenter effects

These are the ways that the experimenter can accidentally influence the participant through their appearance or behavior.

Demand characteristics

The clues in an experiment lead the participants to think they know what the researcher is looking for (e.g., the experimenter’s body language).

Independent variable (IV)

The variable the experimenter manipulates (i.e., changes) is assumed to have a direct effect on the dependent variable.

Dependent variable (DV)

Variable the experimenter measures. This is the outcome (i.e., the result) of a study.

Extraneous variables (EV)

All variables which are not independent variables but could affect the results (DV) of the experiment. EVs should be controlled where possible.

Confounding variables

Variable(s) that have affected the results (DV), apart from the IV. A confounding variable could be an extraneous variable that has not been controlled.

Random Allocation

Randomly allocating participants to independent variable conditions means that all participants should have an equal chance of participating in each condition.

The principle of random allocation is to avoid bias in how the experiment is carried out and limit the effects of participant variables.

Order effects

Changes in participants’ performance due to their repeating the same or similar test more than once. Examples of order effects include:

(i) practice effect: an improvement in performance on a task due to repetition, for example, because of familiarity with the task;

(ii) fatigue effect: a decrease in performance of a task due to repetition, for example, because of boredom or tiredness.

Life is an Experiment: Improving Life Through Experimentation

All of life is an experiment. The more experiments you make the better. – Ralph Waldo Emerson

Life is Like a Box of Chocolates…

We all no doubt experience our fair share of setbacks and disappointments over the course of a lifetime. At one point things are going well, then all of a sudden an error of judgment, a fatal mistake, or an unexpected event can completely derail our efforts. And what seemed like a perfect day has turned into an absolute nightmare. 🙁

Life gets this way at times. In fact, life surprises us with unexpected twists and turns around every corner. This experience was put into words so eloquently by Forrest Gump who said that “life is like a box of chocolates: you never know what you’re gonna get.”

There is another saying that suggests that when bad things happen that we should turn lemons into lemonade, or in other words, we should adapt to the situation and make the most of these circumstances for our own benefit.

These are all of course wonderful ways of looking at life; of looking at failure and setbacks. But how do we get into the necessary frame-of-mind that will help us to think in a more optimal way? How can we begin to cultivate a mindset that will allow us to be open to change and motivated to turn lemons into lemonade?

What if life was an experiment?

Everyone has a certain perspective they bring to life and for that matter to everyday circumstances. By perspective I mean that we all have a certain philosophy that we live by that is built upon very specific beliefs and a certain set of standards and expectations that are either helpful or can potentially hinder our progress.

One such philosophy that I’ve previously discussed comes in the form of seeing life as a game . When we view life as a game we approach everyday events and circumstances in a very specific way. In this instance, we see life as being fun and playful. Moreover, we see it as being very competitive and challenging. And if you’re someone who absolutely loves games and thrives on challenges and a competitive environment, then living in accordance with this philosophy can be of incredible value.

Another philosophy that can be of significant value comes in the form of living life as an experiment. Or to put it another way, it’s all about thinking like a scientist.

Just imagine for a moment facing one of the biggest unexpected setbacks of your life. If you’re like most people you will probably make this situation out to be the end of the world. 🙁 This would typically lead to bouts of stress , anxiety , and worry due to the uncertainty of the situation. Furthermore, this would probably make you feel like a victim of circumstance and would possibly lead to blame, excuses , self-criticism , and a vast array of lousy  complaints . In other words, THE END OF THE WORLD as you know it! Now of course within this state-of-mind it’s incredibly difficult to make the most of the situation and supposedly to turn lemons into lemonade. 🙂

But what if whenever you faced a significant life challenge or any form of adversity you didn’t live by the Victim Mentality Philosophy that most people suffer from. What if you lived by the philosophy that life was nothing more but an experiment and you were the head scientist running the show?

What all this means is that setbacks no longer indicate an end of the road (or of the world), but instead signify that something went wrong with your “life” experiment. As a result, you must now make the necessary adjustments to run the experiment again in order to get a more optimal result.

This is, of course, all well and good. It sounds great in theory to approach life this way, but when the world is falling apart and deep level emotions are brought to the surface the last thing you want to think about is that your life is nothing more but an experiment.

Okay, so how do we do this? How do we start living by the philosophy of living life as an experiment? Well, it all starts with imagining yourself as a scientist.

You are a Scientist

From today onward you are a scientist, and the world is your lab. Within this lab are all your experiments that are tied to various aspects of your life. You are for instance running experiments to help improve your relationships , to earn more money , to pass that exam with flying colors, to convince a friend to buy you lunch, to learn a new skill or language, to overcome that pesky problem , and so much more.

It’s also important to note that every aspect of your life is in combination a grand life experiment. In other words, your entire life is an experiment about living; about living in an optimal way where you try to make the most of every situation in order to help you live life to the very best of your ability.

You are of course the scientist running all these experiments. You get up in the morning and you walk into your lab and begin your experimental work. At times your experiments go horribly wrong (as they do in real life), but that’s okay, it’s after all just an experiment. As you move through each experiment you learn and get better with your experimental work over time.

Now, as a scientist, you cultivate a certain kind of mindset and you have a very specific approach when it comes to working through your life experiments.

As a Scientist you…

See your life as a scientific laboratory. Everything is an experiment and you are always working to improve to make things better. In fact, your underlying objective is not only to improve yourself, but also to make the world a better place.

Don’t fear future outcomes because experiments are unpredictable by their very nature and you wholeheartedly accept that. As such, you are emotionally detached from all desired results. In fact, you clearly understand that even when an experiment goes terribly wrong that there is a lot that can be learned, and at times it can even work to your advantage.

Don’t get easily disappointed , discouraged or frustrated because everything is just an experiment. Sometimes your experiments go as expected, while at other times they don’t. And no matter what happens you never really know whether something is good or bad until much later when you are able to connect all the dots. Negative consequences can at times lead to positive outcomes down the track.

Display patience because that is what experimentation requires from you. As such, you are always grounded, calm and collected no matter what the outcome.

Are continuously testing theories, seeking truths, and challenging your limiting beliefs , false assumptions , and the status quo. What appears to be the truth today may not be true tomorrow after your experiment has concluded. Therefore what you believe now will shift tomorrow and subsequently so will the choices and decisions you make.

Have present moment awareness. In other words, you are very mindful and observant of what is going on around you. Your ability to stay focused allows you to use your keen observation skills to help you see things that the average person typically misses. As such, you can make “on-the-fly” adjustments to your experiments in order to help you make the most of every situation.

Are very open-minded and receptive to new ideas, perspectives and theories. All this stems from your curious nature and willingness to question absolutely everything. Moreover, you typically never accept anything at face value.

Desire improvement and better results each time you run an experiment. You want more fulfilling outcomes that get your creative and problem-solving juices flowing. And of course, when you come across a breakthrough you are excited to share your findings with others.

Living Like a Scientist

As a scientist by nature, you partake in certain rituals and habits that help you get the most from your ability while working through your life experiments.

Within the greater scope of things, your main objective is to study and explore life, nature, and people. You conduct these explorations through studying cause-effect relationships between events, circumstances, and people. Moreover, you also study your own patterns of decision-making , behavior and the subsequent results that evolve. You learn from these observations and make adjustments to help optimize how you live your life.

The underlying key to your explorations and experimentations is to essentially find better ways to get things done. More specifically, it’s all about finding better ways to live your life within your present environment and through your interactions with others. Everything you do is designed to help optimize how you think and process the world around you so that you can make the most of life in every instance.

Your experiments, of course, fail many times over. This is where you take the time to learn from these outcomes in order to improve your future results. You, therefore, have rituals in place that help you think, reflect and assess “what was” in order to make adjustments moving forward.

You, of course, run your experiments in a variety of ways. In fact, you are never satisfied with how things are, and instead push the boundaries of your experiments in order to test new theories that break the grounds of what you previously believed was possible.

Everything you do, everything you are, and every event of your life is a mini-experiment. The bigger the challenge and the bigger the blunder the more excited you get about the possibilities that lie ahead. And of course, every time you fail you get a little giddy inside because you clearly understand that every failed attempt is one step closer to a successful outcome. That, in essence, is what it’s like to live life as a scientist.

Did you know?

Did you know that it has been speculated that Thomas Edison had to undertake approximately 10,000 experiments before he developed the light-bulb? Now, this number might actually have been closer to 1,000 experiments. But even if it was just 1,000 experiments, that’s 1,000 times he failed to create a light-bulb. And do you know what he said after having failed so many times?

I have not failed. I’ve just found 10,000 ways that won’t work. — Thomas Edison

That is essentially what it takes to live life as a scientist.

Then there is the story of how 3M Post-It notes were invented. It’s the story of how a couple of experimental accidents led to the creation of a multi-billion dollar business.

The story begins in 1968 with Spencer Silver who was working to create a super strong adhesive for use in the aerospace industry. However, his experiment didn’t quite go as planned. Instead of developing a super strong adhesive he accidentally created a very weak, pressure sensitive adhesive agent.

This adhesive obviously did not interest 3M because it was too weak to be used for their purposes. However, in time and with a little persistence from Silver it turned into one of the most well known and useful office supply products: The Post-it Note.

Click here to read the full story of how post-it notes were invented.

These are just a couple of examples of the value of experimentation. In the first example, each failure brings you closer to succeeding, and within the second example, an utterly failed botched up experiment led to an incredible breakthrough.

Life, of course, is very much like this. The more you experiment with life the more you’ll learn, and the more you learn the more you know what to avoid doing in order to eventually succeed. Likewise, a horrible failure can lead to an unexpected opportunity that can transform the course of your life in incredible ways.

There is, however, an important factor at play here that makes all this possible. That factor comes in the form of understanding how to ask effective questions that can help you turn lemons into lemonade.

Ask and You Shall Receive…

A scientist’s secret weapon for successful experimentation comes in the form the questions they persistently ask themselves at the beginning, during and after an experiment. These questions help challenge how they think about their experiments, which subsequently allows them to gather relevant data and insights to move their experiments forward.

Now, given that you live your life by the philosophy that life is an experiment, it’s helpful to assume that asking effective questions about yourself, about your life, about other people and circumstances can most certainly help provide you the insights you need to overcome the challenges you face.

As a scientist of your life, you need to challenge yourself daily with new experiments. Some of these experiments will, of course, be forced upon you as a result of circumstance (i.e. setbacks and problems), but at all other times, it’s up to you to figure out what beneficial experiments you can conduct that could potentially help improve your life in a positive way. For instance, you could start by asking yourself:

How could I live a better, happier and more fulfilling life? What experiments could I conduct that would allow me to live life in this way?

These two questions will set the foundations for your experimental work. However, if you’re still challenged for possible experiments you could run, then there are several additional questions that will get your experimental juices flowing:

What if each one of my actions was an experiment? What if my thoughts were an experiment? What if my emotions were an experiment? What if each moment was some kind of experiment? What if all my social interactions were an experiment? What if my life objective was to figure this stuff out?

In order to start living by the philosophy that your life is an experiment, you must put yourself into a receptive state-of-mind that challenges you to think and see everything as a potential experiment. In fact, every part of your life or part of yourself that hasn’t as yet been optimized to its full potential provides an opportunity for experimentation. In other words, anywhere in your life where improvements can be made provides a chance for you to start experimenting in order to improve your results.

The experimental challenges you choose to focus on are of course completely up to you. The key is to focus on making small and incremental improvements that will over time dramatically accelerate your results and help move your life forward in remarkable ways.

Conducting Life Experiments

Have you ever experimented with improving various aspects of your life? You could for instance conduct experiments that help you solve problems more effectively, or create experiments that allow you to resolve conflict, or maybe even prepare experiments that allow you to be more loving, compassionate and caring. Moreover, you could potentially conduct experiments that help boost your productivity , or even experiment with goal achievement to figure out how to best work toward your desired outcomes with the least amount of resistance and effort.

Likewise, you could experiment with how you interact or communicate with different groups of people. You could experiment with changing your schedule to improve your effectiveness and efficiency throughout the day. In fact, you could experiment with various aspects of your lifestyle such as your diet, hobbies, exercise and even with handing addictions.

Every part of your life is open for experimentation as long as the goal is to help you improve yourself or your results in some way.

To set up one of these experiments, all you need to do is:

• First clarify where you’re at, what you have been doing, and the results you have subsequently realized.
• Set a goal for a potential outcome you would like to realize and a date for its accomplishment.
• Lay down a plan of action for achieving that outcome by specifying the daily actions you will take.
• Figure out how you will measure your results and progress. This will help you adjust your course of action when needed.
• Prepare the tools and resources you might need for this experiment.
• Launch your experiment.

Once your experiment is up and running you need to stay very vigilant to measure how things are progressing. Only through rigorous measurement will you understand whether or not you are clearly on track.

Now of course, if this purposeful experimentation makes you feel a little uneasy and somewhat overwhelmed , then that’s perfectly okay. Not all of us are built for this kind of meticulous tracking of our daily behavior and actions.

In order to live by the philosophy of life being an experiment, you don’t necessarily need to run rigorous organized experiments of this nature. What you can do instead is challenge yourself daily in some way. For instance challenge your emotional states , your beliefs , your biases and assumptions, your habits and even your daily thoughts , decisions, and actions.

For example, you could experiment with what it’s like to think more positively when facing adversity . Or how about experimenting with what it’s like to believe that a seemingly impossible problem can be solved? Or potentially experiment with not allowing yourself to get frustrated when things don’t go your way. Choose instead to get curious  by the possibilities.

There are a wide variety of small mini-experiments you can conduct throughout the day that will progressively help to optimize how you think, perceive and interact with the world around you. The key is to just keep an open mind and challenge yourself to begin thinking like a scientist; a scientist that sees no failure, only feedback.

Thinking Like a Scientist

In order to start thinking like a scientist, we must revisit the importance of asking effective questions.

The questions you ask will either lead you to a breakthrough or to a roadblock. However, no matter what potential scenario you face, questions will always help you move forward. They will help you move forward because everything is a form of feedback , and that includes roadblocks.

For instance, when facing a roadblock or major problem a scientist will typically pose “what if…” scenarios. For instance:

What if I try… What then? What if I did this differently? What if I put these two things together? How would things improve if I…?

Alternatively when things don’t work out as expected a scientist will try to understand why things turned out this way and not another way. They will typically ask:

Why didn’t this work? How else could I do this? How else could I solve this problem? How could I improve on this result?

At times though scientists need to dig deeper in order to solve a problem. They may for instance question cause-effect relationships . In such instances they may ask:

What is the relationship between these things? Why did that happen? What led to this event? What affected that? How? What patterns are evident here?

Now of course, no matter how many fantastic insights a scientist gathers from asking these kinds of questions, there always remains the possibility that they are not quite seeing things as clearly as required to help them solve the problem at hand. For instance, they might very well be making assumptions that are preventing them from seeing the truth. In such instances, they will ask themselves:

What assumptions am I making about this? How could my assumptions be hindering me from seeing what is really going on here?

As a scientist moves through their analysis of the problem they are often forced to question every choice they make. And as they question their choices new possibilities come to the surface. You see, for them, nothing is ever clear-cut. There are always alternate possibilities, but unless they question the choices they make, they will never really know what possibilities truly exist.

In the end, the goal is to learn as much as possible from every experiment in order to help improve the results of future experiments. As such, after an experiment has been completed a scientist will typically ask themselves:

What have I learned from this experiment? What will I continue doing as a result? What will I refrain from doing during my next experiment? What will I do differently next time? How?

Whether you’re a scientist working on an experiment or a person living by the philosophy that life is an experiment, you will find tremendous value in asking these kinds of questions.

Concluding Thoughts

Life is all about constant and never-ending improvement . By choosing to live your life as an experiment you are committing yourself to growth and development. With every experiment you conduct you learn a tremendous amount about yourself, about other people, and about the world around you. Moreover, you learn about what works and/or doesn’t work, and can, therefore, make appropriate and necessary adjustments moving forward.

By choosing to live your life as an experiment you are no longer at the mercy of falling into the victim mentality trap. Life just doesn’t happen to you. You are in fact responsible for everything. You are after all part of the experiment; possibly you are the experiment. And as such, you hold the power to change the course and direction of your life.

Yes, life will not always be rosy, in fact, it will bring a lot of hardship and pain. But by taking an experimental approach, you are effectively saying that life will never get the better of you as long as you have the freedom to experiment and improve your circumstances.

Time to Assimilate these Concepts

GET THIS MAP

Did you gain value from this article? Is it important that you know and understand this topic?   Would you like to optimize how you think about this topic? Would you like a method for applying these ideas to your life?

If you answered yes to any of these questions, then I’m confident you will gain tremendous value from using the accompanying IQ Matrix for coaching or self-coaching purposes. This mind map provides you with a quick visual overview of the article you just read. The branches, interlinking ideas, and images model how the brain thinks and processes information. It’s kind of like implanting a thought into your brain – an upgrade of sorts that optimizes how you think about these concepts and ideas. 🙂

Recommended IQ Matrix Bundles

If you’re intrigued by the idea of using mind maps for self-improvement then I would like to invite you to become an IQ Matrix Member.

If you’re new to mind mapping or just want to check things out, then register for the Free 12 Month Membership Program . There you will gain access to over 90 mind maps, visual tools, and resources valued at over $500. 

If, on the other hand, you want access to an ever-growing library of 100s of visual tools and resources, then check out our Premium Membership Packages . These packages provide you with the ultimate visual reference library for all your personal development needs.

Gain More Knowledge…

Here are some additional links and resources that will help you learn more about this topic:

• 7 Lessons Learned from Spending Years Trying to Improve Every Aspect of My Life @ Business Insider
• Drawing Upon Your Own Life Experiments @ CNN
• How do you treat life as an experiment? @ Matthew Cornell
• How to Treat Life Like an Experiment @ The Art of Manliness
• Live Life as an Experiment @ Harvard Business Review
• Why Treating Life Like an Experiment Helps You Make Faster Decisions  @ Fast Company
• Your Life as an Experiment and the Tools to Run it @ Psychology Today

About The Author

Adam Sicinski

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Disney's Live-Action Lilo & Stitch Reveals First Glimpse: 'Experiment 626 Has Entered the Chat'

Maia Kealoha leads Disney's upcoming live-action 'Lilo & Stitch' movie

Disney Studios/Instagram

Lilo & Stitch' s fluffy blue alien is coming to life.

At the D23 fan event in Anaheim, Calif., on Aug. 9, Disney unveiled the first glimpse of the Stitch character design from the upcoming live-action reimagining of Lilo & Stitch.

The reveal comes 22 years after the 2002 animated movie, which follows an alien who crash-lands in Hawaii and finds a new human family.

"Experiment 626 has entered the chat! The live-action #LiloAndStitch is coming only to theaters in Summer 2025!" read a message on the Walt Disney Studios Instagram page.

Newcomer Maia Kealoha portrays Lilo, the human title character, in the movie; Kealoha made her major red carpet debut at the  Gold Gala  on May 11, where she presented an award to first responders who fought the devastating 2023 Maui wildfires .

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer​​, from celebrity news to compelling human interest stories. 

"When I found out I was going to be Lilo, my jaw literally dropped and I couldn't even believe it ," Kealoha told PEOPLE at the time. "I rung my dad and I said, 'I did it! I'm Lilo! I'm Lilo!' And then they grabbed me and we jumped up and down. I was so excited!"

The Hollywood Reporter previously reported that Zach Galifianakis will star in the film, while another newcomer, Kahiau Machado, will portray David Kawena. Sydney Elizebeth Agudong will portray Lilo's older sister Nani.

In April 2023, Deadline reported that Billy Magnussen and Courtney B. Vance will also be in the film, which is directed by Dean Fleischer Camp ( Marcel the Shell With Shoes On ).

Lilo & Stitch is in theaters summer 2025.

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