A paper by current head of the President’s Council of Economic Advisors, Ed Lazear, is significant for what it says near the end about economists forgetting facts, because the facts do not fit into current theory.
(p. 260) Human capital theory is primarily a supply-side approach that focuses on the characteristics and skills of the individual workers. It pays far less attention to the environments in which workers work. As such, the human capital framework has led researchers to focus on one class of questions, but to ignore others. Specifically, little attention has been paid to the jobs in which workers are employed.
(p. 263) The fact that some jobs and some job characteristics are more likely to lead to promotions than other jobs is not surprising. But the analysis suggests that other ways of thinking about wage determination, namely, through job selection, may have been unduly ignored in the past.
. . .
Researchers have begun to make jobs rather than individuals the unit of analysis. This change of focus can illuminate new issues and provide answers to questions that were once posed and forgotten. The questions were forgotten not for lack of importance, but for lack of theoretical frame-works. The theory is now developed and awaits confirmation in the data.
For the full paper, see:
Lazear, Edward P. "A Jobs-Based Analysis of Labor Markets." American Economic Review 85, no. 2 (May 1995): 260-265.
(Note: elipsis added.)