Psych 302

David J. Weiss

Solutions for c² and Confidence Intervals Problem Set 1

1. c² _obs = .80, df = 2. c² _{crit, .05} = 5.99. Color choice is independent of gender

2. c² _obs = 24.06, df = 2. c² _{crit, .05} = 5.99. The distribution of responses has changed from 1960 to 1997.

3. c² _obs = 21.01, df = 1. c² _{crit, .05} =3.84. Married men are more likely to work.

4. $15.87 to $20.33 is a 99% confidence interval for the mean (x = $18.1; s_x = $0.747; t_{crit .01} = 2.977).

5. 150.40 to 170.10 is a 95% confidence interval for the mean (x = 160.25; s_x = 4.62; t_{crit .05} = 2.131).