Produce Design Matrices for Contrasts
Xcontrast(
fit,
a,
b = NULL,
a2 = NULL,
b2 = NULL,
ycut = NULL,
weights = "equal",
expand = TRUE,
Zmatrix = TRUE
)
numeric matrix
an `rms` or `rmsb` fit object, not necessarily complete
see [rms::contrast.rms()]
see [rms::contrast.rms()]
see [rms::contrast.rms()]
see [rms::contrast.rms()]
see [rms::contrast.rms()]
see [rms::contrast.rms()]
see [rms::contrast.rms()]
set to `FALSE` for a partial PO model in which you do not want to include the Z matrix in the returned contrast matrix
Frank Harrell
This is a simpler version of `contrast.rms` that creates design matrices or differences of them and does not require the fit object to be complete (i.e., to have coefficients). This is used for the `pcontrast` option in [rmsb::blrm()].