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ERIC Number: EJ1141308
Record Type: Journal
Publication Date: 2017-Jun
Pages: 11
Abstractor: As Provided
ISSN: ISSN-0013-1644
Three Insights from a Bayesian Interpretation of the One-Sided "P" Value
Marsman, Maarten; Wagenmakers, Eric-Jan
Educational and Psychological Measurement, v77 n3 p529-539 Jun 2017
P values have been critiqued on several grounds but remain entrenched as the dominant inferential method in the empirical sciences. In this article, we elaborate on the fact that in many statistical models, the one-sided "P" value has a direct Bayesian interpretation as the approximate posterior mass for values lower than zero. The connection between the one-sided "P" value and posterior probability mass reveals three insights: (1) "P" values can be interpreted as Bayesian tests of direction, to be used only when the null hypothesis is known from the outset to be false; (2) as a measure of evidence, "P" values are biased against a point null hypothesis; and (3) with "N" fixed and effect size variable, there is an approximately linear relation between "P" values and Bayesian point null hypothesis tests.
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A