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Determining the power of a 1-sided z-test given only the power of the corresponding 2-sided test

Amy Liang1, Kristopher J Preacher2, Nathaniel J Williams3,4

  • 1Department of Psychology and Human Development, Vanderbilt University, 230 Appleton Place, Nashville, TN, 37203‑5721, USA.

Journal of Behavioral Medicine
|September 9, 2025
PubMed

Keywords:
Directional and non-directional hypothesesHypothesis testingPower conversionStatistical power

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