A psychologist conducted a study using a repeated measures design with 15 participants. To analyze the differences in scores between the two conditions, they used a Wilcoxon Signed-Ranks test. One participant's scores were identical in both conditions (difference = 0) and were therefore omitted from the analysis, leaving N=14N = 14N=14.
The hypothesis was non-directional, so a two-tailed test was used at the 0.05 (5%) level of significance.
Using the table of critical values below, state the critical value for this test and explain how you located it.
| NNN | One-tailed, p≤0.05p \le 0.05p≤0.05 | Two-tailed, p≤0.05p \le 0.05p≤0.05 |
|---|---|---|
| 5 | 0 | - |
| 6 | 2 | 0 |
| 7 | 3 | 2 |
| 8 | 5 | 3 |
| 9 | 8 | 5 |
| 10 | 10 | 8 |
| 11 | 13 | 10 |
| 12 | 17 | 13 |
| 13 | 21 | 17 |
| 14 | 25 | 21 |
| 15 | 30 | 25 |
| 16 | 35 | 29 |
513 exam-style questions on OCR A Level Psychology Data recording, analysis and presentation. Each one has a worked solution and a mark scheme showing where the marks go.