statistical power

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sta·tis·ti·cal pow·er

in Neyman-Pearson hypothesis testing, the probability of rejecting the null hypothesis when it is false; the complement of an error of the second kind.

statistical power

probability that a statistical test will reject a false null hypothesis (i.e. that it will not make a type II error)
  • a priori power analysis use of the power calculation from pilot study data, to determine main study sample size

  • post-hoc power analysis use of the power equation from the main study data to determine the power of the study