145. Cheatsheet

Test TypePurposeAssumptionsNon-Parametric EquivalentNon-Parametric Test PurposeNon-Parametric Test Assumptions
One-Sample t-TestCompare sample mean to a known valueNormality of the sample distributionWilcoxon Signed-Rank TestCompare median of a sample to a known valueDistribution-free; does not assume normality
Independent t-TestCompare means between two independent groupsNormality, equal variances in groupsMann-Whitney U TestCompare distributions between two independent groupsDistribution-free; does not assume normality or equal variances
Paired t-TestCompare means between two related groupsNormality of the difference scoresWilcoxon Signed-Rank TestCompare the median of paired differencesDistribution-free; does not assume normality
Two-Sample t-TestCompare means between two independent groupsNormality, equal variances in groupsMann-Whitney U TestCompare distributions between two independent groupsDistribution-free; does not assume normality or equal variances
One-Way ANOVACompare means across three or more groupsNormality, equal variances among groupsKruskal-Wallis TestCompare distributions across three or more independent groupsDistribution-free; does not assume normality or equal variances
Repeated Measures ANOVACompare means across multiple related groupsNormality, sphericity (equal variances of differences)Friedman TestCompare distributions across multiple related groupsDistribution-free; does not assume normality
ANCOVA