A sports scientist investigates whether wearing specialized compression garments reduces muscle soreness in endurance runners. The muscle soreness of 6 elite runners is measured on a 10-point scale (where 10 represents extreme soreness) 24 hours after completing a marathon under two different recovery protocols: a control protocol (standard garments) and an experimental protocol (compression garments). The scientist uses a Wilcoxon Signed-Ranks test to analyze the paired data.
| Runner | Control score | Compression score | Difference | Rank of difference |
|---|---|---|---|---|
| A | 8 | 5 | -3 | 3.5 |
| B | 7 | 3 | -4 | 5 |
| C | 5 | 6 | +1 | 1 |
| D | 9 | 4 | -5 | 6 |
| E | 6 | 3 | -3 | 3.5 |
| F | 4 | 2 | -2 | 2 |
Explain how the critical value is used to determine whether the compression garments significantly reduce muscle soreness when performing a Wilcoxon Signed-Ranks test.
513 exam-style questions on OCR A Level Psychology Data recording, analysis and presentation. Each one has a worked solution and a mark scheme showing where the marks go.