Consider again the one-way ANOVA hypothesis test described in Problem 8. Address the multiple comparison problem by applying the Bonferroni, Tukey, and Scheffé methods to obtain an overall confidence level of approximately 99%. How do these results compare to the uncorrected 99% confidence intervals? Recall that the relevant data are given in the file PDS ILS.

Data from in problem 8

A company sells identical soap in four different packages at the same price. The sales of each package type for 12 months are provided in the file P12_8.XLS. Is there any indication of differences in the mean sales of this brand of soap across the various package types? Perform an appropriate statistical test and report a p-value.