QJE发表的时候脚注写明了"Measuring the social return to R&D " 's previous version was circulated under the title "Too much of a good thing? The economics of investment in R&D "

这两家伙算不算抄袭？

Title: Measuring the social return to R&D
Author(s): Jones CI, Williams JC
Source: QUARTERLY JOURNAL OF ECONOMICS   Volume: 113   Issue: 4   Pages: 1119-1135   Published: NOV 1998
Times Cited: 75
Abstract: Is there too much or too little research and development (R&D)? In this paper we bridge the gap between the recent growth literature and the empirical productivity literature. We derive in a growth model the relationship between the social rate of return to R&D and the coefficient estimates of the empirical literature and show that these estimates represent a lower bound. Furthermore, our analytic framework provides a direct mapping from the rate of return to the degree of underinvestment in research. Conservative estimates suggest that optimal R&D investment is at least two to four times actual investment.

Title: Too much of a good thing? The economics of investment in R&D
Author(s): Jones CI, Williams JC
Source: JOURNAL OF ECONOMIC GROWTH   Volume: 5   Issue: 1   Pages: 65-85   Published: MAR 2000
Times Cited: 39

Abstract: Research and development is a key determinant of long-run productivity and welfare. A central issue is whether a decentralized economy undertakes too little or too much R&D. We develop an endogenous growth model that incorporates parametrically four important distortions to R&D: the surplus appropriability problem, knowledge spillovers, creative destruction, and duplication externalities. Calibrating the model, we find that the decentralized economy typically underinvests in R&D relative to what is socially optimal. The only exceptions to this conclusion occur when the duplication externality is strong and the equilibrium real interest rate is simultaneously high.