A common belief among faculty is that teaching ratings are lower in large classes. Below are MINITAB results from a regression using Y = mean student evaluation of the professor and X = class size for 364 business school classes taught during the 2002­2003 academic year. Ratings are on a scale of 1 (lowest) to 5 (highest).
(a) What do these regression results tell you about the relationship between class size and faculty ratings?
(b) Is a bivariate model adequate? If not, suggest additional predictors to be considered.

Predictor Constant Enroll s-05688 Coef 4.18378 0.000578 R-S4-0.0% SE Coef 0.07226 0.002014 57.90 0.29 0,000 0.774 R-Sq(adj) 0.0%