# A power primer.

@article{Cohen1992APP, title={A power primer.}, author={J. Cohen}, journal={Psychological bulletin}, year={1992}, volume={112 1}, pages={ 155-9 } }

One possible reason for the continued neglect of statistical power analysis in research in the behavioral sciences is the inaccessibility of or difficulty with the standard material. A convenient, although not comprehensive, presentation of required sample sizes is provided here. Effect-size indexes and conventional values for these are given for operationally defined small, medium, and large effects. The sample sizes necessary for .80 power to detect effects at these levels are tabled for…

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