In the data file Stress.dat, available on the Web site, are data on the stress level reported by cancer patients and their spouses at two different times—shortly after the diagnosis and 3 months later. The data are also distinguished by the gender of the respondent. As usual, a “.” indicates each missing data point. See description in Appendix: Computer Data Sets, p. 692.

a. Use any statistical package to run a repeated-measures analysis of variance with Gender and Role (patient versus spouse) as between-subject variables and Time as the repeated measure.

b. Have the program print out cell means, and plot these means as an aid in interpretation.

c. There is a significant three-way interaction in this analysis. Interpret it along with the main effects.