Dr. Sterling’s investigation on weekly screen usage (in hours) and sleep quality index scores among 8 undergraduate students yielded the data shown in Table 1.
Complete Table 2 and calculate Spearman’s rank correlation coefficient (rsr_srs) between the weekly screen usage and the sleep quality index score.
| Student | Screen usage (hours per week) | Sleep quality index |
|---|---|---|
| A | 14 | 42 |
| B | 18 | 35 |
| C | 18 | 38 |
| D | 22 | 28 |
| E | 25 | 28 |
| F | 28 | 20 |
| G | 35 | 15 |
| H | 12 | 45 |
| Screen usage (hours per week) | Rank 1 | Sleep quality index | Rank 2 | ddd | d2d^2d2 |
|---|---|---|---|---|---|
| 14 | 2 | 42 | 7 | ||
| 18 | 3.5 | 35 | 5 | ||
| 18 | 3.5 | 38 | 6 | ||
| 22 | 5 | 28 | 3.5 | ||
| 25 | 6 | 28 | 3.5 | ||
| 28 | 7 | 20 | 2 | ||
| 35 | 8 | 15 | 1 | ||
| 12 | 1 | 45 | 8 | ||
| Total: |
Practise Edexcel A Level Psychology Methods with exam-style questions for A Level Psychology. 638 questions, matched to the Edexcel A Level Psychology (9PS0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.