levene_test Calculates the Levene's test for homogeneity
of variance across groups, model coefficients, the
variance-covariance matrix and the degrees of freedom.
Usage
levene_test(y, x, formula, data)
Value
An object from which the following objects are extracted:
fstats F-test value, including numerator and
denominator degrees of freedom.
qhat model coefficients.
vcov variance-covariance matrix.
dfcom degrees of freedom obtained from df.residual.
Arguments
y
numeric (continuous) response variable.
x
categorical group variable.
formula
A formula object to specify the model as normally
used by glm. Use 'factor' to define the grouping x variable. Only
one variable is allowed.
data
An objects of class milist, created by
df2milist, list2milist or mids2milist.
Author
Martijn Heymans, 2021
Details
The Levene's test centers on group means to calculate
outcome residuals, the Brown-Forsythe test on the median.