The use of p-values in applied research: Interpretation and new trends

Donata Marasini, Piero Quatto, Enrico Ripamonti


In this paper we consider a controversy on the use and interpretation of p-values in applied research. In recent years several applied and theoretical journals have started to discuss on the appropriate use of p-values in research fields such as Psychology, Ecology, and Medicine. First, the notion of p-value has some intrinsic limitations, which have been already highlighted in the statistical literature, but are far from being recognized in applied research. Second, it has emerged the so-called practice of p-hacking, which consists in analyzing and re-analyzing data until obtaining a significant result in terms of a p-value less than 0.05. In the light of these problems, we review two alternative theoretical frameworks, given by the use of Bayes factor and a recent proposal that leads to evaluate statistical hypotheses in terms of a priori and a posteriori odds ratios.


p-value; Neyman-Pearson; Bayes factor; odds ratio; p-hacking

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DOI: 10.6092/issn.1973-2201/6439