Ellen Davis Jones (2003), studied the effects of reminiscence therapy for older women with depression. She studied 15 women 60 years or older residing for 3 months or longer in an assisted living long-term care facility. For this study, depression was measured by the Geriatric Depression Scale (GDS). Higher scores indicate more severe depression symptoms. The participants received reminiscence therapy for long-term care, which uses family photographs, scrapbooks, and personal memorabilia to stimulate memory and conversation among group members. Pre-treatment and posttreatment depression scores are given in the following table. Can we conclude, based on these data, that subjects who participate in reminiscence therapy experience, on average, a decline in GDS depression scores? Use 0.05 level of significance. Pre-GDS: 12 10 16 2 12 18 11 16 16 10 14 21 9 19 20 Post-GDS: 11 10 11 3 9 13 8 14 16 10 12 22 9 16 18