Add the variables (HGT)2 and (AGE × HGT) to the data set for WGT, HGT, AGE, and (AGE)2 given in Section 16.3. Then, using an available regression program and the accompanying computer output, determine the best regression model relating WGT to the five independent variables as follows.
a. Use the forward approach.
b. Use the backward approach.
c. Use an approach that first determines the best model, employing HGT and AGE as the only candidate independent variables, and then determines whether any second-order terms should be added to the model. (Use α = .10.)
d. Compare and discuss the models obtained for each of the three approaches.
Regression Models for Dependent Variable: WGT
SSY = 888.25000, N = 12
Question continues to the next page…