A health psychologist investigated whether using a mindfulness mobile application improves sleep quality. Eight participants rated their sleep quality on a scale of 1 to 15 (where 15 indicates excellent sleep quality) before and after using the application for one week.
Complete Table 2 and calculate the Wilcoxon Signed Ranks TTT value for this study.
Table 2: Sleep quality ratings before and after mindfulness app use
| Participant | Sleep Quality Before | Sleep Quality After | Difference | Rank of Difference (ignoring sign) | Rank if positive | Rank if negative |
|---|---|---|---|---|---|---|
| P | 8 | 11 | ||||
| Q | 12 | 7 | ||||
| R | 9 | 9 | ||||
| S | 10 | 12 | ||||
| T | 5 | 8 | ||||
| U | 13 | 6 | ||||
| V | 7 | 8 | ||||
| W | 11 | 5 | ||||
| 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.