y<-scan('A:/anova_anes.txt') grp<-rep(c(1,2,3,4),c(5,7,9,8)) > grp [1] 1 1 1 1 1 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 cbind(c(table(grp),length(grp)), round(c(mean(y[grp==1]),mean(y[grp==2]),mean(y[grp==3]), mean(y[grp==4]),mean(y)),2), round(c(var(y[grp==1]),var(y[grp==2]),var(y[grp==3]), var(y[grp==4]),var(y)),4) ) [,1] [,2] [,3] 1 5 4.64 1.2080 2 7 4.63 0.7390 3 9 3.53 0.2025 4 8 3.07 0.5479 #Table 3.3 29 3.86 0.9924 > fit<-lm(y~factor(grp)) > anova(fit) Analysis of Variance Table Response: y Df Sum Sq Mean Sq F value Pr(>F) factor(grp) 3 13.0670 4.3557 7.3969 0.001042 ## table 3.4 Residuals 25 14.7213 0.5889