A group of 8 people are being measured on their problem-solving ability (higher scores mean superior ability) before and after participating in a cognitive skills training course. The researchers predict that the people will show a significant benefit of training and increase their scores following participation in the course. Conduct a Wilcoxon Signed Rank test to determine if the peoples' scores increased significantly following training. Assume a two-tailed hypothesis with a = .05.

Before After

Person 1 16 53

Person 2 26 30

Person 3 41 39

Person 4 22 75

Person 5 25 20

Person 6 31 50

Person 7 51 61

Person 8 13 20