Researchers investigating reading comprehension compared a group using printed textbooks (Na=15N_a = 15Na=15) and a group using e-readers (Nb=17N_b = 17Nb=17). They carried out a Mann-Whitney U test to determine if there was a significant difference in comprehension test scores between the two groups.
They used a two-tailed (non-directional) test with a 5% level of significance (p≤0.05p \le 0.05p≤0.05) and determined their observed (calculated) value of U U\,U to be 68.
Explain what this shows in terms of the difference in reading comprehension scores between the printed textbook and e-reader groups.
| NaN_aNa | NbN_bNb | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | ||
| 15 | 51 | 56 | 61 | 64 | 70 | 75 | 81 | 86 | 92 | |
| 16 | 55 | 61 | 66 | 70 | 75 | 81 | 87 | 93 | 99 |
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.