data1 <- read.table("http://www.stat.ufl.edu/~winner/data/menopause_bioavail.dat", header=F,col.names=c("subject","seq","period","trt","carry","auc")) attach(data1); names(data1) subject <- factor(subject) seq <- factor(seq) period <- factor(period) trt <- factor(trt) carry <- factor(carry) mod1 <- lm(auc ~ seq + seq/subject + period + trt + carry) anova(mod1) mod2 <- lm(auc ~ seq + seq/subject + period + carry + trt) anova(mod2) library(lmerTest) mod3 <- lmer(auc ~ seq + period + trt + carry + (1|subject:seq)) summary(mod3) anova(mod3)