insomnia <- read.table(file="http://sites.williams.edu/bklingen/files/2013/12/insomnia.txt", header=TRUE)
attach(insomnia)
outcome <- factor(outcome,levels=1:4,labels=c("20","20-30","30-60","60"), ordered=TRUE)
treat <- factor(treat, levels=0:1,labels=c("Placebo","Active"))
occasion <- factor(occasion, levels=0:1, labels=c("Initial","Follow-Up"))
require("ordinal")
fit <- clmm(outcome~treat*occasion+(1|case), nAGQ=50)
summary(fit)