Sort each statement about p-values as a correct interpretation or a misinterpretation.
Groups: Correct interpretation · Misinterpretation
- p just below and just above 0.05 differ dramatically in what they tell you
- It is the probability that H0 is true
- p = 0.04 proves the effect is large and important
- It is the probability of the data (or more extreme) if H0 is true
- A smaller p-value means the observed result is more surprising under H0
Hints
- A p-value is defined UNDER the null and speaks to surprise, not to effect size or the truth of H0.
- Significance is not the same as importance, and the 0.05 line is not a cliff edge.
Show the answer
Correct interpretation: It is the probability of the data (or more extreme) if H0 is true, A smaller p-value means the observed result is more surprising under H0
Misinterpretation: It is the probability that H0 is true, p = 0.04 proves the effect is large and important, p just below and just above 0.05 differ dramatically in what they tell you
Correct: the p-value is computed under H0 and smaller means more surprising under H0. Misinterpretations: that it is the probability H0 is true, that significance proves a large effect, or that 0.05 is a sharp cliff. Each misreading is a specific, named trap.
Practise Statistical Significance
The app has 6 more questions on this lesson, and keeps your place in the course. Psychology I is free to start.
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