Here are some diagnostic plots for the home prices data from Exercise 15. These were generated by a computer package and may look different from the plots generated by the packages you use. (In particular, note that the axes of the Normal probability plot are swapped relative to the plots we've made in the text. We only care about the pattern of this plot, so it shouldn't affect your interpretation.) Examine these plots and discuss whether the assumptions and conditions for the multiple regression seem reasonable.
In Exercise 15

Dependent Variable is: Asking Price s-67013 R-Sq 71.1% R-Sq ladj)-64.6% Predictor Coeff SECoeff t-ratio P-value Intercept 152037 85619 178 0110 Baths Sa ft 530 40826 139.87 467 3.00 D015 0.23 0821 Analysis of Variance Source DF Regression 2 99303550067 49651775033 11.06 0004 Residual 9 40416679100 4490742122 Total MS F P-value 11 1.39720E+11 Residuals vs, the Fitted Values (Response is Price) 150000 100000 50000. -50000 -100000 100000 200000 300000 400000 Fitted Value Normal Probability Plot of the Residuals (Response is Price) 50000 esidual(S) 50000 100000 150000 Residual (S) Histogram of the Residuals (Response is Price) -50000 0 50000 100000 150000 Residual ($)