set.seed(2332) nk<-4 m.A<-3 m.B<-5 n<-nk*m.A*m.B A<-rep(gl(m.A,m.B),nk) B<-rep(gl(m.B,1,length=m.A*m.B),nk) table(A,B) beta.A<-c(0,2,-1) beta.B<-c(1,1,2,3,1) beta.AB<-matrix(0,nrow=m.A,ncol=m.B) beta.AB[2,2:5]<-0.1 beta.AB[3,2:5]<--0.1 Y<-beta.A[as.numeric(A)]+beta.B[as.numeric(B)]+diag(beta.AB[as.numeric(A),as.numeric(B)])+rnorm(n)*2 table(A,B) fit.bal1<-lm(Y~A*B) summary(fit.bal1) anova(lm(Y~A*B)) anova(lm(Y~B*A)) drop1(fit.bal1,test='F') fit.bal2<-lm(Y~-1+A*B) anova(fit.bal1) anova(fit.bal2) summary(fit.bal2) summary(lm(Y~A)) summary(lm(Y~-1+A)) anova(lm(Y~A)) anova(lm(Y~-1+A)) summary(lm(Y~A+B)) summary(lm(Y~-1+A+B)) anova(lm(Y~A+B)) anova(lm(Y~A+B-1))