rd {survPen}

Defining random effects in survPen formulae

Description

Used inside a formula object to define a random effect.

Usage

rd(...)

Arguments

...

Any number of covariates separated by ","

Value

object of class rd.smooth.spec

Examples

# cubic regression spline of time with 10 unspecified knots + random effect at the cluster level
formula.test <- ~smf(time,df=10) + rd(cluster)