rstatix: friedman_test – R documentation

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friedman_test

Friedman Rank Sum Test

Description

Provides a pipe-friendly framework to perform a Friedman rank sum test, which is the non-parametric alternative to the one-way repeated measures ANOVA test. Wrapper around the function friedman.test(). Read more: Friedman test in R.

Usage

friedman_test(data, formula, ...)

Arguments

`data`	a data.frame containing the variables in the formula.
`formula`	a formula of the form `a ~ b \| c`, where `a` (numeric) is the dependent variable name; `b` is the within-subjects factor variables; and `c` (factor) is the column name containing individuals/subjects identifier. Should be unique per individual.
`...`	other arguments to be passed to the function `friedman.test`.

Value

return a data frame with the following columns:

.y.: the y (dependent) variable used in the test.
n: sample count.
statistic: the value of Friedman's chi-squared statistic, used to compute the p-value.
p: p-value.
method: the statistical test used to compare groups.

Examples

# Load data
#:::::::::::::::::::::::::::::::::::::::
data("ToothGrowth")
df <- ToothGrowth %>%
    filter(supp == "VC") %>%
    mutate(id = rep(1:10, 3))
head(df)

# Friedman rank sum test
#:::::::::::::::::::::::::::::::::::::::::
df %>% friedman_test(len ~ dose | id)

rstatix

Pipe-Friendly Framework for Basic Statistical Tests

v0.7.0

GPL-2

Authors

Alboukadel Kassambara [aut, cre]

Initial release