Below are data showing the results of six subjects on a memory test. The three scores per subject are their scores on three trials (a, b, and c) of a memory task. Are the subjects getting better each trial? Test the linear effect of trial for the data.
| a |
b |
c |
| 4 |
6 |
7 |
| 3 |
7 |
8 |
| 2 |
8 |
5 |
| 1 |
4 |
7 |
| 4 |
6 |
9 |
| 2 |
4 |
2 |
a. Compute L for each subject using the contrast weights -1, 0, and 1. That is, compute (-1)(a) + (0)(b) + (1)(c) for each subject.
b. Compute a one-sample t-test on this column (with the L values for each subject) you created.