1. One sample has SS=48 and a second sample has SS=42.

a. Suppose that n=4 for both samples, find each of sample variances, and compute pooled variance. You must  find that pooled variance is exactly halfway between two sample variances.

b. Now suppose that n=4 for first sample and n=8 for second. Determine each of sample variances, and compute pooled variance. You must find that pooled variance is closer to variance of larger sample (n=8).

Do you view the chocolate bar as delicious or as fattening? Your attitude may depend on gender. In study of American college students, Rozin, Bauer, and Catanese (2003) examined the significance of food as source of pleasure versus concerns about food related with weight gain and health. Following results are similar to those obtained in study. Scores are measure of concern about negative aspects of eating.

Males
N = 6
M = 31
SS = 490
Females
N = 9
M = 45
SS = 680

a. Based on these results, is there significant difference between attitudes for males and for females? Use two tailed test with alpha = .05.

b. Calculate r^2, percentage of variance accounted for by gender difference, to measure effect size for this study.