Simply Psychology
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What Is The Null Hypothesis & When To Reject It
July 31, 2023 - She is also an autistic PhD student ... higher education. ... A null hypothesis is a statistical concept suggesting no significant difference or relationship between measured variables....
Monash University
monash.edu › psychology research portal › research process › 2. investigate your research topic › d. produce a research proposal › aims and hypotheses
Aims and Hypotheses - Psychology Research Portal
The null hypothesis states that there is no relationship between the two variables being studied (one variable does not affect the other).
Videos
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What is a Null Hypothesis? (4 Minute Easy Explanation) - YouTube
03:45
Null Hypothesis | Definition & Examples - Video | Study.com
01:58
Null hypothesis explained - YouTube
24:45
Psychology Statistics: Hypothesis Testing Made Easy - YouTube
15:01
What is the null hypothesis and why do we test it in statistics?
04:15
A Level Psychology - Types of Hypothesis - YouTube
Social psychology journal bans null hypothesis testing
That's not what I was expecting to read. Sure, some journals have banned or limited significance testing. (The American Journal of Public Health did it for a while in the 80s, and Epidemiology has a strong reporting policy.) And Psychological Science recently announced their support for " the new statistics ," meaning an emphasis on effect sizes and confidence intervals instead of p values. But I haven't heard anyone seriously advocate tossing out confidence intervals as well, and then cast doubt on Bayesian statistics too. I don't see how working with solely descriptive statistics will make results more reliable or easier to interpret. Even if CIs are not perfect, surely they're better than providing descriptive point estimates alone? edit: I skimmed the first author's previous paper on Bayesian statistics (Trafimow 2005). It argues that (a) we don't always know a good prior and (b) even then, a flat prior may not make sense, because we don't know if all events are really equally likely. That may be true, but with sufficient data, how does that really matter? Do we really need the prior distribution to be "accurate", whatever that means, or just not obviously stupid? More on reddit.com
Do you have to actually state the null hypothesis in a research proposal?
Yeah thats spot on; no need to state null hypothesis! More on reddit.com
Null hypothesis and Alternative Hypothesis
Hi! So, yours is actually a sophisticated question that masquerades as a simple one, so I'll try to answer this in a way that conveys the concept while perhaps alluding to some of its problems. At its heart, the null hypothesis is a sort of "straw man" that is defined by a researcher at the beginning of an experiment that usually represents a state of affairs that would be expected to occur if the researcher's proposal were false. Note that a null hypothesis is entirely imaginary, and it has nothing to do with the actual state of the world. It is contrived, usually to show that the actual state of the world is inconsistent with the null hypothesis. Suppose a researcher is trying to determine whether the heights of men and women are different. A suitable null hypothesis might be that the difference of the two population averages (height of men and height of women) is equal to zero. Then the researcher would conduct his or her experiment by measuring the heights of many men and women. When it comes time to draw a statistical conclusion, he or she will compute the probability that the observed data (the set of heights) could have come from the null hypothesis (i.e., a world where there is no difference). This probability is called a "p-value". Conceptually, this is similar to a "proof by contradiction," in which we assert that, if the probability is very small that the data could have originated from the null hypothesis, it must not be true. This is what is meant by "rejecting the null hypothesis". It is different from a proof by contradiction because rejecting the null proves nothing, except perhaps that the null is unlikely to be the source of the observed data. It doesn't prove that the true difference is 5 inches, or 1 inch, or anything. Because of this, rejecting the null hypothesis is in NO WAY equivalent to accepting an alternative hypothesis. Usually, in the course of an experiment, we observe a result (such as the observed height difference, perhaps it is ~5 inches) that, once we reject, replaces the hypothesized value of 0 under the null. However, we DON'T know anything about the probability that our observed value is "correct", which is why we never say that we have "accepted" an alternative. I actually hesitate to discuss an "alternative" hypothesis because most researchers never state one and it doesn't matter for the purposes of null hypothesis significance testing (NHST). It is just the name given to the conclusion drawn by the researchers after they have rejected their null hypothesis. Philosophically, there is an adage that data can never be used to prove an assertion, only to disprove one. It includes an analogy about a turkey concluding that he is loved by his human family and is proven wrong upon being slaughtered on Thanksgiving. I'll include a link if I can find it. Now, think about this: The concept of rejecting a null hypothesis probably seems very reasonable as long as we are careful not to overinterpret it, and this is how NHST was performed for decades. But consider - what is the probability that the null hypothesis is true in the first place? In other words, how likely is it that the difference between mens' and womens' heights is equal to zero? I propose that the probability is exactly zero, and if you disagree then I will find a ruler small enough to prove me correct. The difference can never be equal to exactly zero (even though this is the "straw man" that our experiment refutes), so we are effectively testing against a hypothesis that can never be true. Rejecting a hypothesis we already know to be false tells us nothing important ("the data are unlikely to have come from this state that cannot be true"). And since every null hypothesis is imaginary, it is suggested that any null hypothesis can be rejected with enough statistical power (read:sample size). Often a "significant" result says more about a study's sample size than it does about the study's findings, even though the language used in papers/media suggests to readers that the findings are more "important" or "likely to be correct". This has, in part, led to a reproducibility crisis in the sciences and, for some, an undermining of subject-matter-experts' trust in the use of applied statistics. More on reddit.com
Writing a paper with null findings. Does anyone know of any papers with null finding that I can use to see how the discussion is structured? (social psychology preferred)
While this is not exactly what you are looking for, I can recommend this paper wholeheartedly: Quantifying Support for the Null Hypothesis in Psychology: An Empirical Investigation More on reddit.com
What are some problems with the null hypothesis?
One major problem with the null hypothesis is that researchers typically will assume that accepting the null is a failure of the experiment. However, accepting or rejecting any hypothesis is a positive result. Even if the null is not refuted, the researchers will still learn something new.
simplypsychology.org
simplypsychology.org › research methodology › what is the null hypothesis & when do you reject the null hypothesis
What Is The Null Hypothesis & When To Reject It
Why can a null hypothesis not be accepted?
We can either reject or fail to reject a null hypothesis, but never accept it. If your test fails to detect an effect, this is not proof that the effect doesn’t exist. It just means that your sample did not have enough evidence to conclude that it exists.
We can’t accept a null hypothesis because a lack of evidence does not prove something that does not exist. Instead, we fail to reject it.
Failing to reject the null indicates that the sample did not provide sufficient enough evidence to conclude that an effect exists.
If the p-value is greater than the significance level, then you fail to reject the null hypothesis.
We can’t accept a null hypothesis because a lack of evidence does not prove something that does not exist. Instead, we fail to reject it.
Failing to reject the null indicates that the sample did not provide sufficient enough evidence to conclude that an effect exists.
If the p-value is greater than the significance level, then you fail to reject the null hypothesis.
simplypsychology.org
simplypsychology.org › research methodology › what is the null hypothesis & when do you reject the null hypothesis
What Is The Null Hypothesis & When To Reject It
What is the difference between a null hypothesis and an alternative hypothesis?
The alternative hypothesis is the complement to the null hypothesis. The null hypothesis states that there is no effect or no relationship between variables, while the alternative hypothesis claims that there is an effect or relationship in the population.
It is the claim that you expect or hope will be true. The null hypothesis and the alternative hypothesis are always mutually exclusive, meaning that only one can be true at a time.
It is the claim that you expect or hope will be true. The null hypothesis and the alternative hypothesis are always mutually exclusive, meaning that only one can be true at a time.
simplypsychology.org
simplypsychology.org › research methodology › what is the null hypothesis & when do you reject the null hypothesis
What Is The Null Hypothesis & When To Reject It
ScienceDirect
sciencedirect.com › science › article › abs › pii › S0962184904000162
The fallacy of the null hypothesis in soft psychology - ScienceDirect
June 2, 2004 - Null hypothesis significance testing (NHST) has several shortcomings that are likely contributing factors behind the widely debated replication crisis of (cognitive) neuroscience, psychology, and biomedical science in general. We review these shortcomings and suggest that, after sustained negative experience, NHST should no longer be the default, dominant statistical practice of all biomedical and psychological research.
Simply Psychology
simplypsychology.org › research methodology › research hypothesis in psychology: types, & examples
Research Hypothesis In Psychology: Types, & Examples
December 13, 2023 - The null hypothesis states that there will be no significant difference in the amount recalled on a Monday morning compared to a Friday afternoon. Any difference will be due to chance or confounding factors. Memory: Participants exposed to classical music during study sessions will recall more items from a list than those who studied in silence. Social Psychology...
Simple Book Publishing
pdx.pressbooks.pub › psych-research-methods › chapter › understanding-null-hypothesis-testing
Understanding Null Hypothesis Testing – Psychology Research Methods
Describe the basic logic of null hypothesis testing. Describe the role of relationship strength and sample size in determining statistical significance and make reasonable judgments about statistical significance based on these two factors. As we have seen, psychological research typically involves measuring one or more variables in a sample and computing descriptive summary data (e.g., means, correlation coefficients) for those variables.
Wikipedia
en.wikipedia.org › wiki › Null_hypothesis
Null hypothesis - Wikipedia
3 weeks ago - Consider the following example. Given the test scores of two random samples, one of men and one of women, does one group score better than the other? A possible null hypothesis is that the mean male score is the same as the mean female score:
Fiveable
fiveable.me › all key terms › ap psychology › null hypothesis
Null Hypothesis - (AP Psychology) - Vocab, Definition, Explanations | Fiveable
The null hypothesis is a statement that assumes there is no significant relationship or difference between variables being studied. It represents what we expect if there is no effect or relationship in reality.
PsychStix
psychologyrocks.org › hypotheses-directional-and-non-directional
Hypotheses; directional and non-directional – PsychStix
August 27, 2024 - if you were asked for a null hypothesis, make sure you always include the phrase “and any difference/correlation (is your study experimental or correlational?) that does arise will be due to chance alone” · Mr Faraz wants to compare the levels of attendance between his psychology group and ...
tutor2u
tutor2u.net › psychology › reference › research-methods-aims-and-hypotheses
Aims and Hypotheses | Reference Library | Psychology | tutor2u
When the investigation concludes, analysis of results will suggest that either the research hypothesis or null hypothesis can be retained, with the other rejected.
Washington State University
opentext.wsu.edu › carriecuttler › chapter › 13-1-understanding-null-hypothesis-testing
13.1 Understanding Null Hypothesis Testing – Research Methods in Psychology
Describe the basic logic of null hypothesis testing. Describe the role of relationship strength and sample size in determining statistical significance and make reasonable judgments about statistical significance based on these two factors. As we have seen, psychological research typically ...
Simple Book Publishing
kpu.pressbooks.pub › psychmethods4e › chapter › some-basic-null-hypothesis-tests
Some Basic Null Hypothesis Tests – Research Methods in Psychology
August 1, 2019 - The null hypothesis is that the mean estimate for the population (μ) is 250. Because he has no real sense of whether the students will underestimate or overestimate the number of calories, he decides to do a two-tailed test. Now imagine further that the participants’ actual estimates are as follows: ... The mean estimate for the sample (M) is 212.00 calories and the standard deviation (SD) is 39.17. The health psychologist can now compute the t score for his sample:
Open Textbook BC
opentextbc.ca › researchmethods › chapter › some-basic-null-hypothesis-tests
Some Basic Null Hypothesis Tests – Research Methods in Psychology – 2nd Canadian Edition
October 13, 2015 - The null hypothesis is that the mean estimate for the population (μ) is 250. Because he has no real sense of whether the students will underestimate or overestimate the number of calories, he decides to do a two-tailed test. Now imagine further that the participants’ actual estimates are as follows: ... The mean estimate for the sample (M) is 212.00 calories and the standard deviation (SD) is 39.17. The health psychologist can now compute the t score for his sample:
PubMed Central
pmc.ncbi.nlm.nih.gov › articles › PMC5540883
When Null Hypothesis Significance Testing Is Unsuitable for Research: A Reassessment - PMC
Null hypothesis significance testing (NHST) has several shortcomings that are likely contributing factors behind the widely debated replication crisis of (cognitive) neuroscience, psychology, and biomedical science in general. We review these shortcomings and suggest that, after sustained negative experience, NHST should no longer be the default, dominant statistical practice of all biomedical and psychological research.
Taylor & Francis Online
tandfonline.com › home › all journals › mathematics, statistics & data science › journal of the american statistical association › list of issues › volume 94, issue 448 › the null hypothesis testing controversy ....
The Null Hypothesis Testing Controversy in Psychology: Journal of the American Statistical Association: Vol 94, No 448
This article sketches some of the views of statistical theory and practice among different groups of psychologists, reviews a recent book offering multiple perspectives on null hypothesis tests, and argues that the debate within psychology is a symptom of serious incompleteness in the foundations of statistics.
Sage Journals
journals.sagepub.com › doi › 10.1177 › 25152459251365960
Bridging Null Hypothesis Testing and Estimation
September 3, 2025 - Subscription and open access journals from Sage, the world's leading independent academic publisher.
PubMed Central
pmc.ncbi.nlm.nih.gov › articles › PMC5635437
Null hypothesis significance testing: a short tutorial - PMC
Although thoroughly criticized, null hypothesis significance testing (NHST) remains the statistical method of choice used to provide evidence for an effect, in biological, biomedical and social sciences. In this short tutorial, I first summarize the ...