Go back to the information in exercise 11.19. Assuming the conditions for ANOVA are met, test the hypothesis that the mean number of hours of schoolwork varies by class, reporting the p-value and conclusion. Use the 0.05 level of significance. State your conclusion in the context of the data.

Exercise 11.19

Assume you have three groups to compare through hypothesis tests and confidence intervals, and you want the overall level of significance to be 0.05 for the hypothesis tests (which is the same as a 95% confidence level for the confidence intervals).

a. How many possible comparisons are there?

b. What is the Bonferroni-corrected value of the significance level for each hypothesis test?

c. What is the Bonferroni-corrected confidence level for each interval? Report the percentage rounded to two decimal digits, and show your calculations.