image 10.67 Resting metabolic rate and exercise, continued. Refer to the previous exercise. It is tempting to conclude that there is a strong linear relationship for the women but no relationship for the men. Let’s look at this issue a little more carefully.

  1. (a) Find the confidence interval for the slope in the regression equation that you ran for the females. Do the same for the males. What do these suggest about the possibility that these two slopes are the same? (The formal method for making this comparison is a bit complicated and is beyond the scope of this chapter.)

  2. (b) Examine the formula for the standard error of the regression slope given on page 591. The term in the denominator is . Find this quantity for the females; do the same for the males. How do these calculations help to explain the results of the significance tests?

  3. (c) Suppose that you were able to collect additional data for males. How would you use lean body mass in deciding which subjects to choose?