Dr. Vance is a sports psychologist investigating the impact of a novel cognitive visualization technique on the performance of professional drone racing pilots. She recruits 12 participants from a local flight club and randomly assigns them to two groups. Six pilots are assigned to the control group (no visualization training) and six are assigned to the experimental group (completed a 3-week cognitive visualization program). At the end of the program, all pilots complete a standardized high-speed slalom drone racing task, and Dr. Vance records the number of missed gates for each participant. She hypothesizes that pilots using the visualization technique will miss fewer gates than those in the control group.
Dr. Vance decides to perform a Mann-Whitney U test to determine whether the cognitive visualization technique has a significant effect on performance. Table 1 shows the ranked results.
Complete Table 1 and calculate the Mann-Whitney U value for this data.
| Control Group | Experimental Group | ||
|---|---|---|---|
| Missed gates | Rank | Missed gates | Rank |
| 14 | 11.0 | 8 | 4.0 |
| 11 | 7.5 | 6 | 2.0 |
| 15 | 12.0 | 10 | 6.0 |
| 9 | 5.0 | 11 | 7.5 |
| 12 | 9.0 | 5 | 1.0 |
| 13 | 10.0 | 7 | 3.0 |
| Total | Total |
638 exam-style questions on Edexcel A Level Psychology Methods. Each one has a worked solution and a mark scheme showing where the marks go.