cluster {drm} | R Documentation |
This is a special function used in the drm
or depratio
syntax.
It identifies correlated groups of observations, and is used on
the right hand side of a formula.
cluster(x)
x |
A character, factor, or numeric variable. |
The function's only action is semantic, to mark a variable as the cluster indicator.
x
formula(wheeze~cluster(id))