> > tapply(yld,row,mean) 1 2 3 4 5 54.152 56.304 52.288 52.576 57.306 > tapply(yld,col,mean) 1 2 3 4 5 52.434 54.296 54.440 55.298 56.158 > tapply(yld,trt,mean) 1 2 3 4 5 47.134 51.718 55.728 59.168 58.878 > > wheat.mod1 <- aov(yld ~ trt + row + col) > summary(wheat.mod1) Df Sum Sq Mean Sq F value Pr(>F) trt 4 522.30 130.574 27.6685 5.619e-06 *** row 4 99.20 24.801 5.2553 0.0111 * col 4 38.48 9.620 2.0385 0.1527 Residuals 12 56.63 4.719 --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 > TukeyHSD(wheat.mod1,"trt") Tukey multiple comparisons of means 95% family-wise confidence level Fit: aov(formula = yld ~ trt + row + col) $trt diff lwr upr p adj 2-1 4.584 0.2046756 8.963324 0.0387862 3-1 8.594 4.2146756 12.973324 0.0003322 4-1 12.034 7.6546756 16.413324 0.0000120 5-1 11.744 7.3646756 16.123324 0.0000155 3-2 4.010 -0.3693244 8.389324 0.0786064 4-2 7.450 3.0706756 11.829324 0.0011836 5-2 7.160 2.7806756 11.539324 0.0016556 4-3 3.440 -0.9393244 7.819324 0.1539363 5-3 3.150 -1.2293244 7.529324 0.2125524 5-4 -0.290 -4.6693244 4.089324 0.9994896 > >