Question

A researcher uses a repeated-measures design to examine the efficacy of a new Graduate Record Examination (GRE) training program on GRE test scores.

A sample of n = 16 college students is obtained and each student’s performance on the GRE is measured before and after the training program.

The average score increased by M = 15 points after the program with SS = 6000 for the difference scores.

a.) Following the steps of a hypothesis test, first determine whether there was a significant difference in GRE scores before and after the training program. Use α = .05, two-tailed.

b.) Second, calculate Cohen’s d and r2.

c.) Finally, Write a sentence demonstrating how the results of the hypothesis test and the measure of effect size (use either d or r2) would appear in a research report.

Answer 1