Consider again the one-way ANOVA hypothesis test described in Problem 6. Address the multiple comparison problem by applying the Bonferroni, Tukey, and Scheffé methods to obtain an overall confidence level of approximately 99%. Compare the widths of the confidence intervals generated with each of these methods with those of uncorrected 99% confidence intervals. Explain your findings. Recall that the relevant data are given in the file P12_6.XLS.

Data from in problem 6

A professional golf association wants to compare the mean distances traveled by four brands of golf balls when struck by the same driver. Specifically, a robotic golfer uses a driver to hit a random sample of 80 balls (i.e., 20 balls of each brand). Note that the 80 balls are hit in random order. The distance is recorded for each hit, and the results are provided in the file P12_6.XLS.