Author(s)

Sunling Wang^1*, Alejandro Plastina², Lilyan E. Fulginiti³, Eldon Ball¹

¹Economic Research Service, USDA, Washington, DC, USA.
²Department of Economics, Iowa State University, Ames, IA, USA.
³Department of Agricultural Economics, University of Nebraska-Lincoln, Lincoln, NE, USA.

This paper uses panel data for the 1980-2004 period to estimate the contributions of public research to US agricultural productivity growth. Local and social internal rates of return are estimated accounting for the effects of R & D spill-in, extension activities and road density. R & D spill-in proxies were constructed based on both geographic proximity and production profile to examine the sensitivity of the rates of return to these alternatives. We find that extension activities, road density, and R & D spill-ins, play an important role in enhancing the benefit of public R & D investments. We also find that the local internal rates of return, although high, have declined through time along with investments in extension, while the social rates have not. Yet, the social rates of return are not robust to the choice of spill-in proxy.

US Agricultural Productivity, Public R & D, Spill-Ins, Extension, Roads, Internal Rate of Return, Cost Function

Wang, S. , Plastina, A. , Fulginiti, L. and Ball, E. (2017) Benefits of Public R & D in US Agriculture: Spill-Ins, Extension, and Roads. Theoretical Economics Letters, 7, 1873-1898. doi: 10.4236/tel.2017.76128.