#pdf("C:\\Rmisc\\graphs\\kuehl_05_01.pdf")

casting <- c(rep(1:3,each=10))
tstrength <- c(88.0,88.0,94.8,90.0,93.0,89.0,86.0,92.9,89.0,93.0,
               85.9,88.6,90.0,87.1,85.6,86.0,91.0,89.6,93.0,87.5,
               94.2,91.5,92.0,96.5,95.6,93.8,92.5,93.2,96.2,92.5)

alloy <- data.frame(casting,tstrength)

attach(alloy)

casting <- factor(casting)

tapply(tstrength,casting,mean)

tapply(tstrength,casting,sd)

ex_05_01.mod1 <- aov(tstrength ~ casting)

summary(ex_05_01.mod1)

library(nlme)

ex_05_01.mod2 <- lme(fixed=tstrength~1,random=~1|casting)

summary(ex_05_01.mod2)

library(lme4)

ex_05_01.mod3 <- lmer(tstrength~1+(1|casting))

summary(ex_05_01.mod3)

#dev.off()