Record Details

In defense of P values

ScholarsArchive at Oregon State University

Field Value
Title In defense of P values
Names Murtaugh, Paul A. (creator)
Date Issued 2014-03 (iso8601)
Note This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecol.
Abstract Statistical hypothesis testing has been widely criticized by ecologists in recent
years. I review some of the more persistent criticisms of P values and argue that most stem
from misunderstandings or incorrect interpretations, rather than from intrinsic shortcomings
of the P value. I show that P values are intimately linked to confidence intervals and to
differences in Akaike’s information criterion (ΔAIC), two metrics that have been advocated as
replacements for the P value. The choice of a threshold value of ΔAIC that breaks ties among
competing models is as arbitrary as the choice of the probability of a Type I error in
hypothesis testing, and several other criticisms of the P value apply equally to ΔAIC. Since P
values, confidence intervals, and ΔAIC are based on the same statistical information, all have
their places in modern statistical practice. The choice of which to use should be stylistic,
dictated by details of the application rather than by dogmatic, a priori considerations.
Genre Article
Topic AIC
Identifier Murtaugh, P. A. (2014). In defense of P values. Ecology, 95:611–617. doi:10.1890/13-0590.1

© Western Waters Digital Library - GWLA member projects - Designed by the J. Willard Marriott Library - Hosted by Oregon State University Libraries and Press