For Exercises 14.1 and 14.2, see pages 717–718; for 14.3 and 14.4, see page 720; for 14.5 and 14.6, see page 722; for 14.7, see page 724; for 14.8 and 14.9, see page 726; for 14.10 to 14.13, see pages 728–728; for 14.14 and 14.15, see page 731; for 14.16 to 14.19, see page 739; for 14.20 and 14.21, see page 740; for 14.22 and 14.23, see page 741; for 14.24 and 14.25, see page 742; for 14.26 and 14.27, see page 743; for 14.28 and 14.29, see page 744; and for 14.30 and 14.31, see page 748.
14.27 The groups can overlap.
Refer to the previous exercise. Here is another table of means:
| Group | |||
| Group 1 | 128.4 | 9.8 | 20 |
| Group 2 | 138.7 | 13.5 | 20 |
| Group 3 | 143.3 | 15.3 | 20 |
| Group 4 | 131.5 | 11.5 | 20 |
According to the Bonferroni multiple-comparisons procedure with , the means for the following pairs of groups do not differ significantly: 1 and 2, 1 and 4, 2 and 3, 2 and 4. Mark the means of each pair of groups that do not differ significantly with the same letter. Summarize the results.
14.27
Groups 1 and 4 are marked . Group 2 gets both and . Group 3 is marked . Group 3 is the highest and is significantly higher than Groups 1 and 4. Group 2 is caught in between—it is not different from Group 3 nor is it different from Groups 1 and 4.