What Is a Power Analysis in Statistics

Statistical power is the probability of a hypothesis test of finding an effect if there is an effect to be found. A power analysis can be used to estimate the minimum sample size required for an experiment, given a desired significance level, effect size, and statistical power.

What does power analysis mean in statistics?

Power analysis is directly related to tests of hypotheses. The main purpose underlying power analysis is to help the researcher to determine the smallest sample size that is suitable to detect the effect of a given test at the desired level of significance. …

What is the purpose of a power analysis?

The most common reason to conduct a power analysis is to determine the sample size needed for a particular study. However, power analysis may also be used after a study has been completed to determine if the reason an effect was not significant was insufficient power.