Test for Equality of Variances

Performs Levene's test to assess equality of variances between groups.

equal_test(data, var, group, center = "median")

Arguments

data

A data frame containing the variables to be tested.

var

A character string specifying the numeric variable in data to test.

group

A character string specifying the grouping variable in data.

center

A character string specifying the center to use in Levene's test. Default is "median", which is more robust than the mean.

Value

Logical value:

• TRUE: Variances are equal, p-value ≥ 0.05

• FALSE: Variances are unequal or an error occurred during testing

Methodology for Equality of Variances

Levene's test is the default method adopted in SPSS, the original Levene's test select center = mean, but here select center = median for a more robust test

Examples

equal_test(iris, "Sepal.Length", "Species")
#> [1] FALSE