Several years ago we heard about the “Mommy Track,” the phenomenon of women being underpaid in the corporate world because of what is seen as their divided loyalties between home and office. There may also be a “Daddy Differential,” which refers to the situation where men whose wives stay at home earn more than men whose wives work. It is argued that the differential occurs because bosses reward their male employees if they come from “traditional families.” Linda Stroh of Loyola University of Chicago studied a random sample of 348 male managers employed by 20 Fortune 500 companies. Each manager reported whether his wife stayed at home to care for their children or worked outside the home, and his annual income. The incomes (in thousands of dollars) were recorded. The incomes of the managers whose wives stay at home are stored in column 1.

Column 2 contains the incomes of managers whose wives work outside the home.

a. Can we conclude that men whose wives stay at home earn more than men whose wives work outside the home?

b. If your answer in part (a) is affirmative, does this establish a case for discrimination? Can you think of another cause-and-effect scenario? Explain.