Look at the diagnostic plots that proc reg automatically outputs. Do you see any model violations? If so, what violation(s) do you see, and how can you tell?

Fit Diagnostics for Y 2 3 RStudent RStudent Residual Po Observations 75 2 O C Parameters 2 Error DF 73 -2 MSE 0.7697 -2 O 8 R-Square 0.0504 O 1 . O Adj R-Square 0.0374 1.0 1.2 1.4 1.6 1.0 1.2 1.4 1.6 0.02 0.03 0.04 0. 08 82 Predicted Value Predicted Value Leverage O C N 0.15 W 2 0.10 Cook's D Residual -1 0.05 -2 Residuals for Y -1 0.00 O 2 -1 0 2 -1 0 1 2 3 0 20 40 60 O Quantile Predicted Value Observation 2 O 60 Fit-Mean Residual O O 2 O 40 Observations 75 Parameters N O Percent Error DF 73 20 MSE 0.7697 O O R-Square 0.0504 Residual Adj R-Square 0.0374 0 80 O -2.4 -0.8 0.8 2.4 0.0 0.4 0.8 0.0 0.4 0.8 Residual Proportion Less O