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pwrss (version 1.3.1)

Statistical Power, Sample Size, and Detectable Effect Calculations

Description

Flexible and comprehensive functions for statistical power, minimum required sample size, and minimum detectable effect calculations across a wide range of commonly used hypothesis tests in psychological, biomedical, and social sciences.

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install.packages('pwrss')

Monthly Downloads

1,608

Version

1.3.1

License

GPL (>= 3)

Issues

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Stars

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Maintainer

Metin Bulus

Last Published

September 29th, 2026

Functions in pwrss (1.3.1)

power.exact.mcnemar

Power Analysis for McNemar's Exact Test (Paired Proportions)
power.exact.fisher

Power Analysis for Fisher's Exact Test (Independent Proportions)
power.chisq.test

Statistical Power for the Generic Chi-Square Test
means.to.d

Conversion from Means and Standard Deviations to Cohen's d
power.np.wilcoxon

Power Analysis for Non-parametric Rank-Based Tests (One-Sample, Independent, and Paired Designs)
power.f.ancova.keppel

Power Analysis for One-Way ANOVA/ANCOVA Using Means and Standard Deviations (F test)
power.lp.test

Statistical Power for the Lambda-Prime Distribution
power.f.ancova.shieh

Power Analysis for One-, Two-, Three-Way ANCOVA Using Means, Standard Deviations, and (Optionally) Contrasts (F test)
power.f.regression

Power Analysis for Linear Regression: R-squared or R-squared Change (F-Test)
power.f.test

Statistical Power for the Generic F-Test
power.f.ancova

Power Analysis for One-, Two-, Three-Way ANOVA/ANCOVA Using Effect Size (F-Test)
power.t.contrast

Power Analysis for One-, Two-, Three-Way ANCOVA Contrasts and Multiple Comparisons (T-Tests)
power.exact.twoprops

Power Analysis for Testing the Difference Between Two Proportions (Exact Method)
power.f.mixed.anova

Power Analysis for Mixed-Effects Analysis of Variance (F-Test)
power.t.student

Power Analysis for Student's t-Test
power.z.mediation

Power Analysis for Indirect Effects in a Mediation Model (Z, Joint, and Monte Carlo Tests)
power.t.welch

Power Analysis for Welch's t-Test
power.z.oneprop

Power Analysis for the Test of One Proportion (Normal Approximation Method)
power.t.test

Statistical Power for the Generic t-Test
power.t.regression

Power Analysis for Linear Regression: Single Coefficient (T-Test)
power.t.contrasts

Power Analysis for One-, Two-, Three-Way ANCOVA Contrasts and Multiple Comparisons (T-Tests)
power.z.logistic

Power Analysis for Logistic Regression Coefficient (Wald's Z-Test)
power.z.onecor

Power Analysis for One-Sample Correlation
power.z.poisson

Power Analysis for Poisson Regression Coefficient (Wald's z Test)
power.z.twocors.steiger

Power Analysis for Dependent Correlations (Steiger's Z-Test)
probs.to.w

Conversion from Probabilities to Cohen's w
power.z.twocors

Power Analysis for Independent Correlations
power.z.test

Statistical Power for the Generic z-Test
q.to.cors

Conversion from a Cohen's q to a correlation difference
power.z.twoprops

Power Analysis for Testing the Difference Between Two Proportions (Normal Approximation Method)
rsq.to.f

Conversion from R-squared to Cohen's f
z.to.cor

Conversion from a z-value to a correlation (inverse Fisher's z-transformation)
probs.to.h

Conversion from Probability Difference to Cohen's h
inflate.sample

Inflate Sample Size for Attrition
d.to.cles

Conversion from Cohen's d to Common Language Effect Size
lambdap

Distribution functions for the Lambda prime / non-central Lambda distribution
factorial.contrasts

Factorial Contrasts
cors.to.q

Conversion from a correlation Difference to Cohen's q
etasq.to.f

Conversion from Eta-squared to Cohen's f
joint.probs.2x2

Conversion from joint probabilities to marginal probabilities for the McNemar test applied to paired binary data.
f.to.etasq

Conversion between Cohen's f and Eta-squared
cor.to.z

Conversion from a correlation to a z-value (Fisher's z-transformation)
f.to.rsq

Conversion from Cohen's f to R-squared
marginal.probs.2x2

Conversion from marginal probabilities to joint probabilities for the McNemar test applied to paired binary data.
means.to.etasq

Conversion from Means and Standard Deviations to Cohen's f and Eta-squared
power.chisq.gof

Power Analysis for Chi-square Goodness-of-Fit or Independence Tests
power.exact.oneprop

Power Analysis for the Test of One Proportion (Exact Method)
power.binom.test

Power Analysis for the Generic Binomial Test
power.exact.onecor

Power Analysis for One-Sample Correlation (Exact)