Technical change in Senegal's irrigated rice sector: impact assessment under uncertainty
评估塞内加尔灌溉水稻部门技术变革的前景，通过模拟分析新水稻品种的经济回报，发现研究投资在1995-2004年间几乎肯定有高回报，预期内部收益率达121%。
This paper addresses the prospects for technical change in the in·igated rice sector of Senegal, and measures ex-ante the economic returns to recent research efforts. In 1994, three new rice varieties were released to farmers in the Senegal River Valley (SRV), the major irrigated rice region in Senegal. The productivity advantage of the new varieties is based primarily on early maturity, which permits double-cropping. (The seeds are also higher yielding than existing cultivars.) We use a conventional [Akino and Hayami (1975), Am. J. Agric. Econ. 57, l-10] partial-equilibrium model adapted to the Senegalese situation, to assess the social benefits of research and compare those to its costs in calculating the internal rate of return (IRR). To account for uncertainty regarding the future values of model variables we use simulation which allows us to generate a distribution of all possible outcomes of the IRR. We find that rice research is almost certain to have a very high payoff over the 1995-2004 period. The expected value of the IRR is calculated to be 121% per year, with a 97.5% probability that it lies above annual capital costs of 18%. © 2001 Elsevier Science B.V. All rights reserved.