What is a p-value?

This value does not mean the probability the null hypothesis is true.

Anthony B. Masters
3 min readAug 19, 2021

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The p-value is a misunderstood statistic. Sometimes, textbooks carry incorrect definitions — perpetuating misinterpretations.

For example, a Twitter user shared a 2003 biology textbook definition:

The P-value is the bottom line of most statistical tests. It is simply the probability that the hypothesis being tested is true. So if a P-value is given as 0.06, that indicates that the hypothesis has a 6% chance of being true.

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Anthony B. Masters

This blog looks at the use of statistics in Britain and beyond. It is written by RSS Statistical Ambassador and Chartered Statistician @anthonybmasters.