Question

Aresearcher selected a random sample of 10 psychology graduates and found the standard deviation of their grade point average was 0.72. Then she selected a random sample of 14 engineering students and found that the standard deviation of their grade point average was 0.51. At a = 0.01, can we conclude that the variance of the grade point average of the psychology graduates is greater than the variance of the grade point average of the engineering graduates?

Answer 1

Ho: 02-822 ni =10 81=0.72 H: 82702 ng = 14 82 = 0.51 8,2 = (0-72)² 82 = (0.57² Si= ns1² 10 x (0.72) = 10X0.5184 9 10.576 14_40-50% - 10.280 no-1 nirl 10-1 Sg = 2 14-1 1 E = Si 0-576 12.06 S² 0.280 Fontata sool (9, 13 df) = 4.19 Since Feal < Fort so we fail to reject mulu Hypoltesis and claim that teo vanances are quale