Appendix

Comparing two unpaired groups

Table 1: Comparing two unpaired groups (effect size functions from package effectsize, except for wilcoxonR() from rcompanion

Assumption	Test	Function	Effect size	Function
Parametric	T-Test Welch T-Test	t.test(var.equal = TRUE) t.test(var.equal = FALSE)	Cohen’s d	cohens_d()
Non-parametric	Mann-Whitney U	wilcox.test(paired = FALSE)	Rank-biserial r or Wilcoxon R	rank_biserial() or wilcoxonR()

Comparing two paired groups

Table 2: Comparing two unpaired groups (effect size functions from package effectsize, except for wilcoxonPairedR() from rcompanion)

Assumption	Test	Function for test	Effect size	Function for effect size
Parametric	T-Test	t.test(paired = TRUE)	Cohen’s d	cohens_d()
Non-parametric	Wilcoxon Signed Rank Test	wilcox.test(paired = TRUE)	Rank biserial r or Wilcoxon r	rank_biserial() or wilcoxonPairedR()

Comparing multiple unpaired groups

Table 3: Comparing multiple unpaired groups (effect size functions from package effectsize)

Assumption	Test	Function for test	Effect size	Function for effect size
Parametric	ANOVA	aov() (assumes equal variances) oneway.test(var.equal = TRUE/FALSE)	Epsilon squared	eta_squared()
Non-parametric	Kruskall-Wallis test	kruskal.test()	Epsilon squared (rank)	rank_epsilon_squared()