measuring effect size for the repeated measures

The preview section of this chapter presented a repeated-measures research study demonstrating that swearing can help reduce pain (Stephens, Atkins, and Kingston, 2009). In the study, each participant was asked to plunge a hand into icy water and keep it there as long as the pain would allow. In one condition, the participants repeated their favorite curse words while their hands were in the water. In the other condition, the participants repeated a neutral word.Data similar to the results obtained in the study are shown in the following table: Amount of Time (in seconds) Participant Swear Words Neutral Words 1 94 59 2 70 61 3 52 47 4 83 60 5 46 35 6 117 92 7 69 53 8 39 30 9 51 56 10 73 61

a. Do these data indicate a significant difference in pain tolerance between the two conditions? Use a two-tailed test with α = .05. b. Compute r^2, the percentage of variance accounted for, to measure the size of the treatment effect. c. Write a sentence demonstrating how the results of the hypothesis test and the measure of effect size would appear in a research report.