Extract or remake model matrix from model and potentially change the contrast coding
get_model_matrix(model, type = c("extract", "remake"), contrasts = "restore")the model (or 'design') matrix.
an lm or lmerMod model object.
extract or remake model matrix?
contrasts settings. These may be restored to those in the
model or they may be changed. If a length one character vector (e.g.
"contr.SAS") this is applied to all factors in the model, but it can
also be a list naming factors for which the contrasts should be set as specified.
Rune Haubo B Christensen