Solutions Statistics

Solution) Suppose we’re interested in the effect of practice on public speaking anxiety. We recruit eight volu

Question: Suppose we’re interested in the effect of practice on public speaking anxiety. We recruit eight volunteers and pretest them on public speaking anxiety on a standardized test. We then provide the volunteers with several practice sessions in giving speeches and test them again. To see if the practice causes a lasting change in their anxiety, we administer a follow-up test 6 months later. Here are the data (higher scores indicate higher anxiety):

	Pretest	Posttest	Follow-up
Volunteer 1	8	6	7
Volunteer 2	6	4	5
Volunteer 3	5	5	7
Volunteer 4	7	7	2
Volunteer 5	7	4	5
Volunteer 6	3	1	2
Volunteer 7	10	6	4
Volunteer 8	10	7	8