powered by
Used inside a formula object to define a random effect.
rd(...)
object of class rd.smooth.spec
rd.smooth.spec
Any number of covariates separated by ","
# cubic regression spline of time with 10 unspecified knots + random effect at the cluster level formula.test <- ~smf(time,df=10) + rd(cluster)
Run the code above in your browser using DataLab