A clinical psychologist wants to investigate whether a cognitive training programme improves memory performance. She tests a group of 15 participants before and after they complete the programme, measuring their memory performance using a ranked self-assessment questionnaire (producing ordinal data).
Which statistical test should the psychologist use to determine if there is a significant difference in memory performance?
Mann–Whitney U test
Related ttt-test
Wilcoxon Signed Ranks test
Sign test
644 exam-style questions on OCR A Level Psychology Research methods and techniques. Each one has a worked solution and a mark scheme showing where the marks go.