The Economic impact of public agricultural research and development in the United States
研究了美国公共农业研发投资与生产率提升的关系，估计了知识生产率函数，并计算出年实际回报率在8%到10%之间。
Abstract In this article, we examine the relationship between public investments in agricultural research and development and the productivity‐enhancing benefits they generate. Knowledge productivity functions are estimated for U.S. agriculture using data on multifactor productivity and public knowledge stocks. We examine the time‐series properties of the data and compare alternative econometric estimation procedures. The results are used to calculate economic performance measures such as internal rates of return and benefit‐cost ratios. The real rate of return to public investments in agricultural research and development in the United States is in the range of 8–10% per annum.