fbrglm - Safe Formula-Based Regularized Generalized Linear Models
A formula-based wrapper around 'glmnet' that brings the
'glm()'-compatible modeling workflow to regularized generalized
linear models. Training-time 'terms', 'xlevels', and
'contrasts' are stored on the fit object and reused at predict
time, so the design matrix is reconstructed consistently across
sessions. Complete-case bookkeeping is exposed via 'nobs_info',
and linearly dependent columns are detected by a QR pivot and
reported as 'NA' in 'coef()' and 'summary()' (the
'stats::glm()' convention), distinguishing "not identifiable"
from "shrunk to zero by the penalty". Novel factor levels at
predict time raise the same error 'stats::predict.glm()' does
by default, with 'on_new_levels = "na"' as a production-style
opt-in. Accepts character family strings ('gaussian',
'binomial', 'poisson', 'cox', 'multinomial', 'mgaussian') and
any 'glm' family object the underlying 'glmnet' itself accepts,
including 'Gamma' and fixed-theta negative binomial via
'MASS::negative.binomial'.