Posted by daniel on .
2. On a certain anxiety questionnaire, the population is known to have a mean of 12 and a standard deviation of 2.3. A higher score represents higher levels of anxiety. Participants in a new relaxation program complete the questionnaire after completing the program, and have a mean score of 10.2. What is the effect size of the relaxation program?

Statistics 
PsyDAG,
See previous post.