a formula giving the terms to be considered for adding or dropping.
test
the type of test to include.
method
Indicates which method is used for computing the standard
error. robust is the default and corresponds to the modified sandwich
estimator. naive is the classical naive cariance estimate.
sandwich is an alias for robust.
…
other arguments. Not currently used
Value
An object of class "anova" summarizing the differences in fit
between the models.