Describe Relationship: Numeric x by Categorical g

Computes descriptive statistics for a numeric variable x grouped by a categorical variable g.

Usage

.descNQ(x, g, ...)

# S3 method for class 'Desc.nq'
print(x, digits = NULL, ...)

# S3 method for class 'Desc.nq'
plot(x, main = x$meta$main, which = NULL, ...)

Arguments

x

a numeric variable

digits

number of digits used to format relative frequencies

...

further arguments, currently unused

main

main title for the plot; defaults to the title stored in x$meta$main

which

integer vector selecting which plots to draw. See Details. NULL (default) selects plots automatically based on verbose.

g

a categorical grouping variable (factor or coercible to factor)

Value

an object of class c("Desc.nq", "Desc") with components:

tab

group-wise summary table

test

result of the Kruskal-Wallis test

vtest

result of Levene's test

eta

effect size

Details

The function summarizes the distribution of x across levels of g and performs nonparametric tests of group differences.

Computed statistics

• Group-wise descriptive statistics (mean, median, SD, IQR, counts)

• Kruskal-Wallis test

• Effect size (\(\eta^2\)) based on the Kruskal-Wallis statistic

• Levene's test for homogeneity of variance

Interpretation The Kruskal-Wallis test evaluates whether the distribution of x differs between groups defined by g. The effect size \(\eta^2\) provides a standardized measure of group differences.

See also

desc, desc.qn, desc.nn, pharos::plot.Desc.qn kruskal.test, lumen::leveneTest

Other desc: desc(), desc.Date(), desc.factor(), desc.nn, desc.numeric(), desc.qn, desc.qq, desc.table(), desc.ts()