# The earth is round (p < .05)

@article{Cohen1994TheEI, title={The earth is round (p < .05)}, author={Jacob Cohen}, journal={American Psychologist}, year={1994}, volume={49}, pages={997-1003} }

After 4 decades of severe criticism, the ritual of null hypothesis significance testing (mechanical dichotomous decisions around a sacred .05 criterion) still persists. This article reviews the problems with this practice, including near universal misinterpretation of p as the probability that H₀ is false, the misinterpretation that its complement is the probability of successful replication, and the mistaken assumption that if one rejects H₀ one thereby affirms the theory that led to the test…

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