Dr. Vance's investigation on daily caffeine intake and self-reported anxiety scores among 10 university students yielded the data shown in Table 1.
Complete Table 2 and calculate Spearman's rank correlation coefficient (rsr_srs) between daily caffeine intake and anxiety score.
| Student | Daily caffeine intake (mg) | Anxiety score |
|---|---|---|
| A | 100 | 12 |
| B | 150 | 14 |
| C | 150 | 15 |
| D | 200 | 16 |
| E | 250 | 18 |
| F | 300 | 20 |
| G | 350 | 25 |
| H | 400 | 25 |
| I | 200 | 18 |
| J | 300 | 22 |
| Daily caffeine intake (mg) | Rank 1 | Anxiety score | Rank 2 | ddd | d2d^2d2 |
|---|---|---|---|---|---|
| 100 | 1 | 12 | 1 | ||
| 150 | 2.5 | 14 | 2 | ||
| 150 | 2.5 | 15 | 3 | ||
| 200 | 4.5 | 16 | 4 | ||
| 250 | 6 | 18 | 5.5 | ||
| 300 | 7.5 | 20 | 7 | ||
| 350 | 9 | 25 | 9.5 | ||
| 400 | 10 | 25 | 9.5 | ||
| 200 | 4.5 | 18 | 5.5 | ||
| 300 | 7.5 | 22 | 8 | ||
| 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.