A cognitive psychologist investigated the impact of ambient scents on problem-solving speed using a repeated measures design, where the same group of participants completed tasks under two different environmental conditions.
The psychologist recorded the time taken (in seconds) by each participant to successfully complete the puzzles.
Table 1: Mean completion times (seconds) and standard deviations
| Lavender scent | Peppermint scent | |
|---|---|---|
| Mean | 145.8 | 122.4 |
| Standard deviation | 22.5 | 15.3 |
Explain how using counterbalancing might improve the design of this study.
Practise AQA A Level Psychology Scientific processes with exam-style questions for A Level Psychology. 100 questions, matched to the AQA A Level Psychology (7182) 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.