Exam 11: Multiple Comparisons and Analysis of Variance

Suppose that you wish to compare the mean starting salaries of students from seven different majors based on a random sample of students from these majors. There will be a total of 21 pairwise comparisons. Using the Bonferroni Correction, what significance level should you use for each hypothesis test if you want an overall significance level of 0.05? Round your answer to the nearest thousandth.

Choose the appropriate test for the following situation. A company has instituted a new work policy that it hopes will reduce the number of sick days used per year by its employees. You wish to test whether the mean number of sick days used by employees this year differs from the mean number of sick days used last year by all employees (which was 8.2).

Choose the statement that is not true about multiple comparisons and ANOVA. Choose (d) if all the statements are true.

Name the appropriate test for the following situation: Suppose that researchers wish to study whether type of diet affects alertness levels. Three popular dieting plans were included in the study. After following the diet for several weeks, participants were given a test that measured response time to a stimulus.

Use the following information to answer questions (17) - (19). Researchers want to test whether the color of a vehicle ticketed for speeding has an effect on the amount of the ticket. Four vehicle colors were used for the study - red, white, black, and silver. Thirty vehicles were randomly assigned to each group. Use the output below to answer questions (17) - (19). One-way ANOVA Variance between groups = 2063.33 Variance within gr p-value = 0.000239 oups = 296.25 -Do the ANOVA test results warrant a Post-hoc procedure?

Name the appropriate test for the following situation: You wish to test whether an association exists between type of vehicle transmission purchased- automatic or manual- and gender of the purchaser.

What is the meaning of the overall significance level of a test? Explain what happens to the overall significance level when multiple comparisons are made, that is, when multiple hypothesis tests are conducted in an effort to compare the means of several groups.

Choose the statement that is not true about ANOVA.

Choose the statement that best describes the purpose of ANOVA.

Use the following information to answer questions (17) - (19). Researchers want to test whether the color of a vehicle ticketed for speeding has an effect on the amount of the ticket. Four vehicle colors were used for the study - red, white, black, and silver. Thirty vehicles were randomly assigned to each group. Use the output below to answer questions (17) - (19). One-way ANOVA Variance between groups = 2063.33 Variance within gr p-value = 0.000239 oups = 296.25 -Compute the F-statistic. Round to the nearest hundredth.

Describe two of the four conditions that must be checked in order for the calculated F-statistic to follow the F-distribution.

What is the test statistic used for the ANOVA procedure? Explain how it is calculated.

Suppose you wish to compare the means of m groups pair-by-pair. Choose the statement that is not true about the Bonferroni Correction. Choose (d) if none of the statements is true.

Choose the appropriate test for the following situation: You wish to test whether an association exists between the type of vehicle purchased and the number of children the buyer has.