[NOTE: This is a repost of a blog that Andrew Gelman wrote for the blogsite Statistical Modeling, Causal Inference, and Social Science]. Blake McShane and David Gal recently wrote two articles (“ Blinding us to the obvious? The effect of statistical training on the evaluation of evidence” and “Statistical significance and the dichotomization of evidence”) on the misunderstandings of p-values that are common even among supposed experts in statistics and applied social research.