Knowledge that Transforms

Much of the male-female wage differential exists because men and women are assigned to different jobs. Within narrow job categories, there is no male-female differential. Only a tortured taste theory of discrimination can reconcile these facts. We argue that differential movement along job ladders entails comparative advantage, so the ability standard for promotion is higher for women. This implies that more able women will be passed over in favor of less able men. Women, assumed to have the same ability distribution as men, earn less. The differential reflects females' lower promotion probability, not within-job discrimination.

The "human capital earnings function," in which earnings are expressed as a quadratic in potential experience, is probably the most widely accepted empirical specification in economics. In spite of its widespread acceptance, the human capital earnings function provides a very poor approximation of the true empirical relationship between earnings and experience. The standard formulation understates early career earnings growth by about 30%-50% and overstates midcareer growth by 20%-50%. However, simple alternative specifications that fit the data are available.

For more than a decade, there has been a great debate in the profession concerning the proper base for personal and business taxation. This debate has focused on the choice of the base versus the (or consumption) base. The concept of used in these debates is a comprehensive accretion measure often referred to as HaigSimons income, after the work of Robert M. Haig (1921) and Henry C. Simons (1938). This is the standard concept of income that has been used (with several variations) in tax policy analysis in the postwar period. However, it appears not to be widely recognized that, although Haig did ultimately settle on accretion income as the best feasible tax base, he definitely saw this as a second-best measure of true income. As will become clear, reexamination of Haig's famous article reveals that Haig actually felt that consumption expenditure would be a better measure of true income than accretion income, and he would have preferred a tax on this base-that is, he preferred what today would be called a consumption tax. He felt that