(a) In the family lung function data in Appendix A divide the fathers into two groups: group I with FEV1 less than or equal to 4.09, and group II with FEV1 greater than 4.09. Assuming equal prior probabilities and costs, perform a stepwise discriminant function analysis using the variables height, weight, age, and FVC. What are the probabilities of misclassification?

(b) Use the classification function you found in part

(a) to classify first the mothers and then the oldest children. What are the probabilities of misclassification? Why is the assumption of equal prior probabilities not realistic?