Chapter 7 EARNINGS FUNCTIONS, RATES OF RETURN AND TREATMENT EFFECTS: THE MINCER EQUATION AND BEYOND1 JAMES J. HECKMAN Department of Economics, University of Chicago, 1126 East 59th Street, Chicago, IL 60637, USA e-mail:
[email protected] LANCE J. LOCHNER Department of Economics, University of Western Ontario, 1151 Richmond Street N, London, ON, N6A 5C2, Canada e-mail:
[email protected] PETRA E. TODD Department of Economics, University of Pennsylvania, 20 McNeil, 3718 Locust Walk, Philadelphia, PA 19104, USA e-mail:
[email protected] Contents Abstract 310 Keywords 310 1. Introduction 311 2. The theoretical foundations of Mincer’s earnings regression 315 2.1. The compensating differences model 315 2.2. The accounting-identity model 316 Implications for log earnings–age and log earnings–experience profiles and for the inter- personal distribution of life-cycle earnings 318 1 Heckman is Henry Schultz Distinguished Service Professor of Economics at the University of Chicago and Distinguished Professor of Science and Society, University College Dublin. Lochner is Associate Professor of Economics at the University of Western Ontario. Todd is Professor of Economics at the University of Pennsylvania. The first part of this chapter was prepared in June 1998. It previously circulated under the title “Fifty Years of Mincer Earnings Regressions”. Heckman’s research was supported by NIH R01-HD043411, NSF 97-09-873, NSF SES-0099195 and NSF SES-0241858. We thank Christian Belzil, George Borjas, Pedro Carneiro, Flavio Cunha, Jim Davies, Reuben Gronau, Eric Hanushek, Lawrence Katz, John Knowles, Mario Macis, Derek Neal, Aderonke Osikominu, Dan Schmierer, Jora Stixrud, Ben Williams, Kenneth Wolpin, and participants at the 2001 AEA Annual Meeting, the Labor Studies Group at the 2001 NBER Summer Institute, and participants at Stanford University and Yale University seminars for helpful comments.