Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
This paper examines the evolution of productivity in U.S. manufacturing plants from 1963 to 1992. We define a vintage effect as the change in productivity of recent cohorts of new plants relative to earlier cohorts of new plants, and a survival effect as the change in productivity of a particular cohort of surviving plants as it ages. Both factors contribute to industry productivity growth, but play offsetting roles in determining a cohort's relative position in the productivity distribution. Recent cohorts enter with higher productivity than earlier entrants did, whereas surviving cohorts show productivity increases as they age. These two effects roughly offset each other, however, so there is a rough convergence in productivity across cohorts in 1992 and 1987. © 2001 by the President and Fellows of Harvard College and the Massachusetts Institute of Technology