remission<-data.frame(rem=c(18,27,14,25),sex=factor(c(1,1,2,2)),
treat=factor(c(1,2,1,2)),n=c(30,30,30,30))
remission
fit1<-glm(cbind(rem,n-rem)~sex*treat,family = binomial(link = logit),
        data=remission)
summary(fit1)
anova(fit1,test="Chisq")
fit2<-update(fit1,.~.-sex:treat)
summary(fit2)
anova(fit2,test="Chisq")