An International Journal of Research (March 2010) study of the impact of reality TV shows on a college student's decision to undergo cosmetic surgery, Exercise 12.43. The data saved in the file were used to fit the interaction model, E(y) = β0 + β1x1 + β2x4 + β3x1x4, where y = desire to have cosmetic surgery (25-point scale), x1 = {1 if male, 0 if female}, and x4 = impression of reality TV (7-point scale). From the SPSS printout, the estimated equation is:
 = 11.78 - 1.97x1 + .58x4 - .55x1x4
a. Give an estimate of the change in desire (y) for every 1-point increase in impression of reality TV show (x4) for female students.
b. Repeat part a for male students.