In an essay of 250-500 words, use the scenario presented in part 1a, above, to thoroughly answer the following questions:
1. What statistical test did the researchers use to determine if there was a statistically significant difference in levels of self-esteem between the boys and the girls?
2. What was the purpose of calculating a Cohen's d? When is a Cohen's d calculated? Interpret d=.90. What does it mean in this example?
3. What if the researcher compared the adolescent boys before treatment and again after treating them for depression? What type of t-test would be most appropriate in this case, and why?