Suppose the USGA tests four different brands (A, B, C, D) of golf balls and two different clubs (driver, five-iron) in a 4 * 2 factorial design. Each of the eight Brand-Club combinations (treatments) is randomly and independently assigned to four experimental units, each consisting of a specific position in the sequence of hits by Iron Byron. The distance response is recorded for each of the 32 hits, and the results are shown in Table 10.13. LO4 Distance Data for 4 : 2 Factorial Golf Experiment Brand Club A B C D Driver 226.4 238.3 240.5 219.8 232.6 231.7 246.9 228.7 234.0 227.7 240.3 232.9 220.7 237.2 244.7 237.6 Five-iron 163.8 184.4 179.0 157.8 179.4 180.6 168.0 161.8 168.6 179.5 165.2 162.1 173.4 186.2 156.5 160.3 Conducting a Factorial ANoVA—
Golf Ball Driving Distances Example 10.10

a. Use statistical software to partition the total sum of squares into the components necessary to analyze this 4 * 2 factorial experiment.

b. Conduct the appropriate ANOVA tests and interpret the results of your analysis.
Use a = .10 for the tests you conduct.

c. If appropriate, conduct multiple comparisons of the treatment means. Use an experimentwise error rate of .10. Illustrate the comparisons with a graph.