An educational psychologist investigated whether a new spaced-repetition vocabulary app increases the number of words recalled in a foreign language test. Table 1 shows the vocabulary test scores (out of 20) of 11 students measured before and after using the app for a month.
| Student | Score before | Score after |
|---|---|---|
| Student A | 12 | 15 |
| Student B | 9 | 14 |
| Student C | 15 | 18 |
| Student D | 11 | 16 |
| Student E | 14 | 12 |
| Student F | 8 | 13 |
| Student G | 10 | 10 |
| Student H | 13 | 17 |
| Student I | 7 | 11 |
| Student J | 11 | 15 |
| Student K | 16 | 19 |
When using a Wilcoxon Signed-Ranks Test to analyze the difference, the calculated value of T T\,T was found to be 5 (T=5T = 5T=5).
| NNN | p≤0.05p \le 0.05p≤0.05 (one-tailed) | p≤0.05p \le 0.05p≤0.05 (two-tailed) |
|---|---|---|
| 9 | 8 | 5 |
| 10 | 10 | 8 |
| 11 | 13 | 11 |
Using the data in Table 1 and Table 2, explain whether the results are significant at p≤0.05 p \le 0.05\,p≤0.05 for a directional (one-tailed) hypothesis, and if the researcher's directional hypothesis can be accepted.
638 exam-style questions on Edexcel A Level Psychology Methods. Each one has a worked solution and a mark scheme showing where the marks go.