Relevel a Factor's Reference Level

Standalone helper for choosing the reference (baseline) level of a factor before passing it to [cox_single()] or [cox_multi()]. Wraps [stats::relevel()], defaulting to the first level (matching the reference-row convention already used by cox_single()/cox_multi()), and attaches a "cbe_reference_level" attribute recording the chosen level.

Usage

relevel_factor(x, ref_level = NULL)

Arguments

x

A factor, or a vector coercible to one via as.factor().

ref_level

Character string naming the level to use as reference. Defaults to the first level of x (its current or natural ordering).

Value

The releveled factor, with attribute "cbe_reference_level" set to the chosen reference level.

Details

cox_single() and cox_multi() are not rewired to require this helper; it is an optional convenience for callers who want to choose the reference level explicitly before fitting.

See also

[cox_single()], [cox_multi()]