An interface designer investigated whether a new "Yoke-style" headband design reduced physical neck discomfort compared to a standard "Halo-style" headband during extended virtual reality (VR) sessions. She conducted a laboratory study with a sample of 18 participants.
In Condition 1 (Halo), participants wore the standard headband while playing a VR simulation for 30 minutes, then rated their neck discomfort on a subjective scale from 1 (no discomfort at all) to 15 (extreme discomfort).
In Condition 2 (Yoke), the same 18 participants played the same VR simulation for 30 minutes wearing the new headband, then rated their neck discomfort using the same 1 to 15 scale.
The order in which participants experienced the two headbands was counterbalanced.
To determine if there was a significant reduction in discomfort, the designer analysed the paired ratings using a Wilcoxon signed-ranks test.
Explain two reasons why it was appropriate to use a Wilcoxon signed-ranks test in this study. Refer to the description of the study in your answer.
121 exam-style questions on AQA A Level Psychology Inferential testing (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.