12.21 The following model was fitted to a sample of 25 students using data obtained at the end of their freshman year in college. The aim was to explain students’

weight gains:

y = b0 + b1x1 + b2x2 + b3x3 + e where y = weight gained, in pounds, during freshman year x1 = average number of meals eaten per week x2 = average number of hours of exercise per week x3 = average number of beers consumed per week The least squares estimates of the regression parameters were as follows:

b0 = 7.35 b1 = 0.653 b2 = -1.345 b3 = 0.613 The regression sum of squares and error sum of squares were found to be as follows:

SSR = 79.2 and SSE = 45.9

a. Compute and interpret the coefficient of determination.

b. Compute the adjusted coefficient of determination.

c. Compute and interpret the coefficient of multiple correlation.