ANOVA Problem Sheet1) Auditors must make judgments about various aspects of an audit on the basis of theirown direct experience, indirect experience, or a combination of the two. In a study, auditorswere asked to make judgments about the frequency of errors to be found in anaudit. The judgments by the auditors were then compared to the actual results. Supposethe following data were obtained from a similar study; lower scores indicate betterjudgments.

Direct Indirect Combination17.0 16.6 25.218.5 22.2 24.015.8 20.5 21.518.2 18.3 26.820.2 24.2 27.516.0 19.8 25.813.3 21.2 24.2

Use =.05 to test to see whether the basis for the judgment affects the quality of the judgment.What is your conclusion?

2) Four different paints are advertised as having the same drying time. To check the manufacturersclaims, five samples were tested for each of the paints. The time in minutes untilthe paint was dry enough for a second coat to be applied was recorded. The following datawere obtained.Paint 1 Paint 2 Paint 3 Paint 4128 144 133 150137 133 143 142135 142 137 135124 146 136 140141 130 131 153At the =.05 level of significance, test to see whether the mean drying time is the samefor each type of paint.

3) A well-known automotive magazine took three top-of-the-line midsize automobiles manufacturedin the United States, test-drove them, and compared them on a variety of criteria. In the area of gasoline mileage performance, five automobiles of each brand were eachtest-driven 500 miles; the miles per gallon data obtained follow. Use = .05 to test whether there is a significant difference in the mean number of miles per gallon for thethree types of automobiles. AutomobileA B C19 19 2421 20 2620 22 2319 21 2521 23 27

4) The following data are from an experiment designed to investigate the perception of corporateethical values among individuals specializing in marketing (higher scores indicatehigher ethical values).

Marketing Managers Marketing Research Advertising6 5 65 5 74 4 65 4 56 5 64 4 6

a. Use =.05 to test for significant differences in perception among the three groups.b. At the = .05 level of significance, we can conclude that there are differences in theperceptions for marketing managers, marketing research specialists, and advertisingspecialists. Use the procedures in this section to determine where the differencesoccur. Use = .05.

5) To test for any significant difference in the number of hours between breakdowns for fourmachines, the following data were obtained.

Machine 1 Machine 2 Machine 3 Machine 46.4 8.7 11.1 9.97.8 7.4 10.3 12.85.3 9.4 9.7 12.17.4 10.1 10.3 10.88.4 9.2 9.2 11.37.3 9.8 8.8 11.5

Is there a significant difference between the mean times?