Gestational period and life expectancy revisited The data in the Animals file on the book’s website holds observations on the average longevity (in years) and gestational period

(in days) for a variety of animals. Exercise 3.52 showed the scatterplot together with the regression equation with intercept 6.29 and slope 0.045 and an r2 value of 0.73.

a. Interpret the slope.

b. A leopard has a gestational period of about 98 days.

What is its predicted average longevity?

c. Interpret the value of r2.

d. Show that extrapolating from animals to humans

(with gestational period of about 40 weeks) grossly underestimates average human longevity.