Discussion:
Q: A researcher studies the effect of cognitive psychotherapy on positive self-regard. The number of positive statements made about oneself is recorded for each participant during the first meeting. After 8 weekly therapy sessions, the measures are repeated for each person. For the following data.
Participant before treatment after treatment
A 7 10
B 6 13
C 9 12
D 5 8
a. Calculate the difference scores and Md
b. Compute SS, sample variance, and estimated standard error
c. Is there a significant treatment effect? Use ±=.05, two tails.