Refer to Exercise 17.10, where a multiple regression analysis was performed to predict men’s longevity based on the parents’ and grandparents’ longevity. In addition to these data, suppose that the actuary also recorded whether the man was a smoker (1 = yes and 0 = no).

a. Use regression analysis to produce the statistics for this model.

b. Compare the equation you just produced to that produced in Exercise 18.10. Describe the differences.

c. Are smoking and length of life related? Explain.

In exercise 17.10

 Life insurance companies are keenly interested in predicting how long their customers will live because their premiums and profitability depend on such numbers. An actuary for one insurance company gathered data from 100 recently deceased male customers. He recorded the age at death of the customer plus the ages at death of his mother and father, the mean ages at death of his grandmothers, and the mean ages at death of his grandfathers.