Public R&D, private R&D, and U.S. agricultural productivity growth: dynamic and long-run relationships.

摘要

This study uses long-term time series data on public and private agricultural R&D spending in the USA to examine their relationship with one another and to agricultural productivity growth. The study finds econometric evidence of complementarity between public and private agricultural research investments, with both sectors responsive to what the other sector is doing (or not doing). Increased spending on public fundamental or applied crop research appears to stimulate an increase in private research on crops, possibly because of new technological opportunities for commercialization opened up by public research. At the same time, public crop research appears to decline following an exogenous increase in private crop research, possibly because the public sector withdraws from areas it sees private companies pursuing. Other results from the study confirm that research affects agricultural productivity only over the long term. Changes in either public or private research expenditure have no significant impact on agricultural TFP growth, but research stocks (accumulation of several years of research expenditures) do. However, due to the high collinearity between public and private agricultural research stocks (even with 40 years of time series data), it remains difficult to estimate the respective impacts of public and private research on productivity.Digital Object Identifier http://dx.doi.org/10.1093/ajae/aat032