Manipulating the alpha level cannot cure significance testing – comments on "Redefine statistical significance"
- Published
- Accepted
- Subject Areas
- Science Policy, Statistics
- Keywords
- P-value, Significance, NHST, Alpha level, Threshold, Publication bias, Winner’s curse, Replicability, Bayes factor, Statistics
- Copyright
- © 2017 Trafimow et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2017. Manipulating the alpha level cannot cure significance testing – comments on "Redefine statistical significance" PeerJ Preprints 5:e3411v1 https://doi.org/10.7287/peerj.preprints.3411v1
Abstract
We argue that depending on p-values to reject null hypotheses, including a recent call for changing the canonical alpha level for statistical significance from .05 to .005, is deleterious for the finding of new discoveries and the progress of science. Given that blanket and variable criterion levels both are problematic, it is sensible to dispense with significance testing altogether. There are alternatives that address study design and determining sample sizes much more directly than significance testing does; but none of the statistical tools should replace significance testing as the new magic method giving clear-cut mechanical answers. Inference should not be based on single studies at all, but on cumulative evidence from multiple independent studies. When evaluating the strength of the evidence, we should consider, for example, auxiliary assumptions, the strength of the experimental design, or implications for applications. To boil all this down to a binary decision based on a p-value threshold of .05, .01, .005, or anything else, is not acceptable.
Author Comment
This is a reply to Benjamin et al. 2017. Redefine statistical significance. Nature Human Behaviour 1, 0189.