Chapter 10.3, Problem 36PB

Body dissatisfaction test Refer to the previous exercise.

1. a. Find the P-value for testing whether the population means are equal. Use a two-sided alternative.
2. b. Summarize assumptions for the analysis in part a. Do you think the normality assumption is justified? If not, what is the consequence of violating it?

10.35 Body dissatisfaction Female college student participation in athletics has increased dramatically over the past few decades. Sports medicine providers are aware of some unique health concerns of athletic women, including disordered eating. A study (M. Reinking and L. Alexander, Journal of Athletic Training, vol. 40, 2005, pp. 47–51) compared disordered-eating symptoms and their causes for collegiate female athletes (in lean and nonlean sports) and nonathletes. The sample mean of the body dissatisfaction assessment score was 13.2 (s = 8.0) for 16 lean sport athletes (those sports that place value on leanness, including distance running, swimming, and gymnastics) and 7.3 (s = 6.0) for the 68 nonlean sport athletes. Assuming equal population standard deviations,

1. a. Find the standard error for comparing the means.
2. b. Construct a 95% confidence interval for the difference between the mean body dissatisfaction for lean sport athletes and nonlean sport athletes. Interpret.