Force the variables you selected in Problem 9.9(a) into the regression equation with OCFEV1 as the dependent variable, and test whether including the FEV1 of the parents (i.e., the variables MFEV1 and...

Force the variables you selected in Problem 9.9(a) into the regression equation with OCFEV1 as the dependent variable, and test whether including the FEV1 of the parents (i.e., the variables MFEV1 and FFEV1 taken as a pair) in the equation significantly improves the regression.

PROBLEM 9.9

(a) For the lung function data set described in Appendix A with age, height, weight, and FVC as the candidate independent variables, use subset regression to find which variables best predict FEV1 in the oldest child. State the criteria you use to decide. (b) Repeat, using forward selection and backward elimination. Compare with part (a).