Data Analysis with R, Second Edition - Second Edition

A warning about p-values

P-values are, by far, the most talked about metric in NHST. P-values are also notorious for lending themselves to misinterpretation. Of the many criticisms of NHST (of which there are many, in spite of its ubiquity), the misinterpretation of p-values ranks highly. The following are two of the most common misinterpretations:

1. Myth: A p-value is the probability that the null hypothesis is true. This is not the case. Someone misinterpreting the p-value from our first binomial test might conclude that the chances of the coin being fair are around 10%. This is false. The p-value does not tell us the probability of the hypothesis' truth or falsity. In fact, the test assumes that the null hypothesis is correct. It tells ...