The ANOVA in this chapter compares the yield of 5 varieties of wheat. In fact, the Colorado trials in- volved 54 varieties! Suppose our grower in eastern Colorado was interested in comparisons among all 54 varieties, not just 5. (Assume 8 plots for each variety, so n = 8 * 54 = 432.)
(a) How many dummy variables would be needed as explanatory variables in the regression?
(b) Suppose that se = 4.217 bushels per acre, as in the text analysis of five varieties. With so much more data, are the Tukey and Bonferroni con- fidence intervals for the differences in average yields longer or shorter than those in the analysis of five varieties?