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Paperpal
paperpal.com › home › how to write a hypothesis? types and examples
How to Write a Hypothesis? Types and Examples | Paperpal
October 7, 2025 - For example, “There is a positive association between physical activity levels and overall health.” A causal hypothesis, on the other hand, expresses a cause-and-effect association between variables. For example, “Long-term alcohol use causes liver damage.” · Null: Claims that the original hypothesis is false by showing that there is no relationship between the variables.
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Simply Psychology
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
July 31, 2023 - Krueger, J. (2001). Null hypothesis significance testing: On the survival of a flawed method. American Psychologist, 56(1), 16.
Discussions

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
🌐 r/statistics
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June 1, 2014
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
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January 5, 2021
People also ask

What is null hypothesis testing and when should a null hypothesis be rejected?
A4. Null hypothesis testing is a method to decide between two assumptions or predictions between variables (null and alternative hypotheses) in a statistical relationship in a sample. · The null hypothesis, denoted as H0, claims that no relationship exists between variables in a population and any relationship in the sample reflects a sampling error or occurrence by chance. · The alternative hypothesis, denoted as H1, claims that there is a relationship in the population. In every study, researchers need to decide whether the relationship in a sample occurred by chance or reflects a relationsh
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paperpal.com
paperpal.com › home › how to write a hypothesis? types and examples
How to Write a Hypothesis? Types and Examples | Paperpal
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.
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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 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.
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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
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Online Learning College
online-learning-college.com › home › gcses › gcse psychology › hypotheses
Hypotheses | What Is A Hypothesis?, Null & Alternative Hypotheses
January 27, 2025 - For example, a psychologist may predict that children who listen to music whilst revising will do better in their exams than those children who do not. There are two types of hypotheses, which are null ...
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Helpful Professor
helpfulprofessor.com › home › 15 null hypothesis examples
15 Null Hypothesis Examples (2025)
August 26, 2023 - For instance, a company might use a null hypothesis to test if a new marketing strategy improves sales. If data suggests a significant increase in sales, the null hypothesis is rejected, and the new strategy may be implemented.
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ThoughtCo
thoughtco.com › null-hypothesis-examples-609097
How to Formulate a Null Hypothesis (With Examples)
May 7, 2024 - It's essentially the opposite of the null hypothesis because it assumes the claim in question is true. For the first item in the table above, for example, an alternative hypothesis might be "Age does have an effect on mathematical ability."
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Statistics By Jim
statisticsbyjim.com › home › blog › null hypothesis: definition, rejecting & examples
Null Hypothesis: Definition, Rejecting & Examples - Statistics By Jim
November 7, 2022 - For these tests, the null hypothesis states that there is no difference between group proportions. Again, the experimental conditions did not affect the proportion of events in the groups. P is the population proportion parameter that you’ll need to include. For example, a vaccine experiment compares the infection rate in the treatment group to the control group.
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Lumen Learning
courses.lumenlearning.com › suny-bcresearchmethods › chapter › some-basic-null-hypothesis-tests
Some Basic Null Hypothesis Tests | Research Methods in Psychology
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 ...
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Scribbr
scribbr.com › home › null and alternative hypotheses | definitions & examples
Null & Alternative Hypotheses | Definitions, Templates & Examples
January 24, 2025 - The alternative hypothesis (Ha) answers “Yes, there is an effect in the population.” · The null and alternative are always claims about the population. That’s because the goal of hypothesis testing is to make inferences about a population based on a sample.
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Washington State University
opentext.wsu.edu › carriecuttler › chapter › 13-1-understanding-null-hypothesis-testing
13.1 Understanding Null Hypothesis Testing – Research Methods in Psychology
Explain for someone who knows nothing about statistics why the researchers would conduct a null hypothesis test. Practice: Use Table 13.1 to decide whether each of the following results is statistically significant. The correlation between two variables is r = −.78 based on a sample size of 137. The mean score on a psychological characteristic for women is 25 (SD = 5) and the mean score for men is 24 (SD = 5).
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Indeed
uk.indeed.com › career guide › career development › null hypothesis examples (plus uses and importance)
Null hypothesis examples (plus uses and importance) | Indeed.com UK
1 week ago - Null hypothesis: Footballers are not more likely to suffer leg injuries over the course of their careers compared with cricketers. Here are some examples of alternative hypotheses that assume a relationship between the variables:Question: Are dogs better at catching balls than cats?
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National University
resources.nu.edu › statsresources › hypothesis
Null & Alternative Hypotheses - Statistics Resources - LibGuides at National University
October 27, 2025 - Alternative Hypothesis: Ha: Male factory workers have a higher salary than female factory workers. Null Hypothesis: H0: There is no relationship between height and shoe size.
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Laerd Statistics
statistics.laerd.com › statistical-guides › hypothesis-testing-3.php
Hypothesis Testing - Significance levels and rejecting or accepting the null hypothesis
The null hypothesis is essentially ... it usually states that something equals zero). For example, the two different teaching methods did not result in different exam performances (i.e., zero difference)....
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PubMed Central
pmc.ncbi.nlm.nih.gov › articles › PMC2996198
Hypothesis testing, type I and type II errors - PMC
The null hypothesis is rejected in favor of the alternative hypothesis if the P value is less than alpha, the predetermined level of statistical significance (Daniel, 2000). “Nonsignificant” results — those with P value greater than alpha — do not imply that there is no association in the population; they only mean that the association observed in the sample is small compared with what could have occurred by chance alone. For example, an investigator might find that men with family history of mental illness were twice as likely to develop schizophrenia as those with no family history, but with a P value of 0.09.
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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: Individuals who frequently engage in social media use will report higher levels of perceived social isolation compared to those who use it infrequently.
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Study.com
study.com › courses › psychology courses › psychology 105: research methods in psychology
Null Hypothesis | Definition & Examples - Video | Study.com
January 5, 2016 - For example, Little Susie's hypothesis about flowers is that when she uses club soda, the flowers will grow faster than regular water. She then continued this experiment for a month, proving her hypothesis right.
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Numiqo
numiqo.com › tutorial › hypothesis
Hypothesis: A Beginner’s Guide
October 27, 2025 - For example, the eye color is a variable, it is the property of the object eye and can take different values (blue, brown,...). If you are researching in the social sciences, your variables may be: ... There are always two hypotheses that are exactly opposite to each other, or that claim the opposite. These opposite hypotheses are called null and alternative hypothesis ...
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Fiveable
fiveable.me › all key terms › intro to psychology › hypothesis testing
Hypothesis Testing - (Intro to Psychology) - Vocab, Definition, Explanations | Fiveable | Fiveable
By formulating a null hypothesis ... statistically test these hypotheses. For example, in evaluating the effectiveness of a new therapy for depression, the null hypothesis might be that the therapy has no effect on symptoms, while the alternative hypothesis would be that the ...
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Simple Book Publishing
pdx.pressbooks.pub › psych-research-methods › chapter › understanding-null-hypothesis-testing
Understanding Null Hypothesis Testing – Psychology Research Methods
The p value is one of the most misunderstood quantities in psychological research (Cohen, 1994)[2]. Even professional researchers misinterpret it, and it is not unusual for such misinterpretations to appear in statistics textbooks! The most common misinterpretation is that the p value is the probability that the null hypothesis is true—that the sample result occurred by chance. For example, a misguided researcher might say that because the p value is .02, there is only a 2% chance that the result is due to chance and a 98% chance that it reflects a real relationship in the population.