Definition: Free to use statistical software for performing power analyses. The user specifies the desired statistical test (e.g. t-test, regression, ANOVA), and three of the following: the number of groups/observations, effect size, significance level, or power, in order to calculate the unspecified aspect.

Related terms: Power analysis, Sample size justification, Sample size planning, <a href='/glossary/statistical-power/'>Statistical power</a>

References: Faul et al. (2007), & Faul et al. (2009)

Drafted and Reviewed by: Filip Dechterenko, Thomas Rhys Evans, Kai Krautter, Charlotte R. Pennington

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