kwallis: Kruskal-Wallis Test

In R4VN: Health Data Analysis and Publication-Ready Reporting

Kruskal-Wallis Test

Description

Performs the Kruskal-Wallis rank-sum test for a numeric outcome across two or more independent groups. Optional Dunn or pairwise Wilcoxon post-hoc tests and rank-based effect sizes can be requested. With by = vars(region, sex, treatment), region and sex are nested strata and treatment is the innermost Kruskal-Wallis factor.

Usage

kwallis(
  x, by, data = NULL, posthoc = c("none", "dunn", "wilcoxon"),
  adjust = "holm", effect = FALSE, digits = 3, p_digits = 3, show = TRUE,
  console = FALSE
)

Arguments

x	Numeric outcome.
by	Grouping variable with at least two observed groups, or hierarchical vars(...) specification.
data	Data frame. If NULL, active R4VN data is used.
posthoc	Post-hoc method: "none", "dunn", or "wilcoxon".
adjust	Multiplicity adjustment accepted by stats::p.adjust().
effect	Logical; add epsilon-squared and eta-squared(H).
digits, p_digits	Decimal places for estimates and p-values.
show	Logical; open the formatted result in the Viewer. Default TRUE.
console	Logical; also print the traditional result in the Console. Default FALSE.

Value

Invisibly returns an object of class r4vn_stat.

Examples

d <- data.frame(
  score = c(10, 12, 11, 18, 17, 20, 25, 24, 27),
  group = factor(rep(c("A", "B", "C"), each = 3))
)
kwallis(score, by = group, data = d, posthoc = "dunn", effect = TRUE)

# Extended usage examples

d <- data.frame(
  score = c(10, 12, 11, 18, 17, 20, 25, 24, 27),
  treatment = factor(rep(c("A", "B", "C"), each = 3))
)
kwallis(score, by = treatment, data = d)
usedf(d)
result <- kwallis(score, by = treatment, show = FALSE)
result$raw$test

R4VN documentation built on Sept. 30, 2026, 5:13 p.m.