Data from an Oats Field Trial
The yield of oats from a split-plot field trial using three varieties and four levels of manurial treatment. The experiment was laid out in 6 blocks of 3 main plots, each split into 4 sub-plots. The varieties were applied to the main plots and the manurial treatments to the sub-plots.
Yates, F. (1935) Complex experiments, Journal of the Royal Statistical Society Suppl. 2, 181--247.
Also given in Yates, F. (1970) Experimental design: Selected papers of Frank Yates, C.B.E, F.R.S. London: Griffin.
Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S. Fourth edition. Springer.
oats$Nf <- ordered(oats$N, levels = sort(levels(oats$N))) oats.aov <- aov(Y ~ Nf*V + Error(B/V), data = oats, qr = TRUE) summary(oats.aov) summary(oats.aov, split = list(Nf=list(L=1, Dev=2:3))) par(mfrow = c(1,2), pty = "s") plot(fitted(oats.aov[]), studres(oats.aov[])) abline(h = 0, lty = 2) oats.pr <- proj(oats.aov) qqnorm(oats.pr[][,"Residuals"], ylab = "Stratum 4 residuals") qqline(oats.pr[][,"Residuals"]) par(mfrow = c(1,1), pty = "m") oats.aov2 <- aov(Y ~ N + V + Error(B/V), data = oats, qr = TRUE) model.tables(oats.aov2, type = "means", se = TRUE)