depr<-read.table("http://sites.williams.edu/bklingen/files/2012/02/depression.txt",header=TRUE)
str(depr)

# Marginal model fitting
# use GEEPACK package
require(geepack)
fit_exch <- geeglm(outcome~severity+drug+time+drug*time,family=binomial,id=case,data=depr,corstr="exchangeable")
summary(fit_exch)
anova(fit_exch)
fit_ar1 <- geeglm(outcome~severity+drug+time+drug*time,family=binomial,id=case,data=depr,corstr="ar1")
summary(fit_ar1)
fit_unstr <- geeglm(outcome~severity+drug+time+drug*time,family=binomial,id=case,data=depr,corstr="unstructured")
summary(fit_unstr)

#GLMM (probably did not have time to do in class!!)
require(glmmML)
fit <- glmmML(outcome~severity+drug+time+drug*time, family=binomial, data=depr, cluster=case, prior = "gaussian", method = "ghq", n.points=50)