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arXiv · 1311.0081

To P or not to P: on the evidential nature of P-values and their place in scientific inference

Michael J. Lew
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Abstract

The customary use of P-values in scientific research has been attacked as being ill-conceived, and the utility of P-values has been derided. This paper reviews common misconceptions about P-values and their alleged deficits as indices of experimental evidence and, using an empirical exploration of the properties of P-values, documents the intimate relationship between P-values and likelihood functions. It is shown that P-values quantify experimental evidence not by their numerical value, but through the likelihood functions that they index. Many arguments against the utility of P-values are refuted and the conclusion is drawn that P-values are useful indices of experimental evidence. The widespread use of P-values in scientific research is well justified by the actual properties of P-values, but those properties need to be more widely understood.

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Michael J. Lew. 2013-11-01. To P or not to P: on the evidential nature of P-values and their place in scientific inference. https://arxiv.org/abs/1311.0081

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