Refer to Exercise 13.34. As happens in many studies, not all the data are correctly collected. The researcher decides that errors are present in the information collected at several of the homes. After eliminating the questionable data values, the data appropriate for modeling are given here.

a. Fit a cubic model y = β0 + β1x + β2x2 + β3x3 + ɛ to the reduced data set.
b. Compare the fit of the model in Exercise 13.35 to the fit of the model in part (a).
In exercise

y 16 1 7 40 263305 65 130 18 123 1 113 3 3 6 6 9 1 12 12 y 99 113 10S 109 5 134 05 133 99 95 149 160 r 15 15 15 8 18 21 2 24 24 30 30 y 16 12 740 26 33 98 105 65 130 90 109 10 118 123 x 1 1 13 3 3 6 6 6 99 9 12 12 12 y 99 113 105 90 109 115 134 105 129 119 133 99 195 149 160 x 15 15 15 18 18 18 21 21 21 24 24 24 30 30 30