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991.
This paper analyzes a model of aid allocation equalizing the opportunity between recipient countries to reach a common poverty reduction goal. We propose a fair and efficient aid allocation based on a multicriteria principle. The model considers structural handicaps in recipient countries in terms of lack of human capital and economic vulnerability, their initial poverty, and the natural gap between the growth rate required to reach a development goal and the observed one. We show that our proposed aid allocation favors poor and vulnerable countries with our multicriteria principle. It substantially differs from the observed allocation. Analyses also shed light on the impact of the donors' aversion to the low natural growth gap in recipient countries on the optimal aid allocation and the marginal efficiency of aid.  相似文献   
992.
993.
This article examines the impact of public agricultural research and extension on agricultural total factor productivity at the state level. The objective is to establish whether federal formula or competitive grant funding of agricultural research has a greater impact on state agricultural productivity. A pooled cross-section time-series model of agricultural productivity is fitted to annual data for forty-eight contiguous states over 1970–1999. Our results show that public agricultural research and agricultural extension have statistically significant positive impacts on state agricultural productivity. In addition, Hatch formula funding has a larger impact on agricultural productivity than federal competitive grant funding, and a reallocation of Hatch formula funds to competitive grant funding would lower agricultural productivity. This seems unlikely to be a socially optimal policy. Furthermore, from a cost–benefit perspective, our study shows that the social marginal annualized real rate of return to public resources invested in agricultural research is 49–62%, and to public agricultural extension, the rate is even larger.  相似文献   
994.
Among the different factors pertaining to the demand for durable inputs in agriculture, the way the input depreciates over time is an important issue. This study investigates four alternative capacity depreciation patterns for farm tractors. While published estimates from government agencies implicitly assume convex capacity depreciation patterns, the results of this study demonstrate that the use of agricultural engineering data which depict a concave rather than convex pattern better reflect farmers' investment decisions. An implicit rental price measure is also proposed to account for the fact that the purchase price of a durable input is not an appropriate measure of the implicit rental cost of the asset.
Parmi les facteurs déterminants de la demande pour les biens durables en agriculture, la rapidité avec laquelle I'intrant se déprécie est certainement importante lors des décisions d'investissement. La présente etude analyse quatre différents scénarios de dépréciation pour les tracteurs agricoles au Canada. Bien que les données publiées par les agences gouver-nementales supposent implicitement que les biens durables se déprécient à un taux annuel constant, les résultats de cette etude montrent que I'utilisation de données basées sur la valeur productive de I'intrant telle que calculée sur une base expkrimentale donne de meil-leurs résultats statistiques dans I'estimation de la demande pour les tracteurs agricoles. De plus, une mesure du coût implicite de I'intrant est également proposée pour tenir compte du fait que le prix d'achat n'est pas une mesure appropriée dans I'analyse de la demande pour un bien durable.  相似文献   
995.
The National School Lunch Program is not meeting its nutritional goals. Data for 330 Minnesota school districts are analyzed to derive recommendations for improving the nutritional quality of school lunches. This study finds, contrary to widely held views, that lunch sales do not decline when healthier meals with less fat, for example, are served and that more nutritious lunches do not necessarily cost more. Healthier meals have higher labor costs, but lower costs for processed foods. Indirect costs, paid by the food service to the school district, negatively affect meal quality by decreasing funds to upgrade kitchens and train staff to prepare more nutritious meals.  相似文献   
996.
Optimal trade policy in an uncertain world is examined. Decision-maker attitudes toward uncertainty are represented in terms of the Gilboa–Schmeidler (1989) maximin expected-utility (MMEU) model. The central result is that in a two-country, general-equilibrium setting with both trading partners possessing an MMEU preference structure, Pareto optimality can require one trading partner to absorb all uncertainty in the economy if its set of priors is a subset of its trading partners. An immediate corollary is that autarky is Pareto optimal if the trading partner with the more inclusive set of priors either chooses or is endowed with a nonstochastic technology.  相似文献   
997.
Soils in a large part of Niger's agricultural area are sandy and very low in nitrogen (N), phosphorus (P) and organic matter. This low soil fertility combined with low and erratic rainfall constitutes a severe constraint on food cropping in the area. Although agronomists have advised chemical fertilization as a means of improving soil fertility, little fertilizer has been used in this area of the world. The economic management of soil fertility in the agricultural area of Niger is analyzed using a dynamic model of farmer decision-making under uncertainty. The model is based on agronomic principles of plant growth and accounts for the carry over of P, an immobile nutrient. At current input prices, a soil P content of at least 14 ppm is found to be desirable. This target is above the natural soil fertility level of about 3 ppm. It can be maintained with a moderate annual application (12 kg P2O5 ha?1) of simple superphosphate. Results also suggests that returns to N fertilization are too low and variable to warrant the use of this input.  相似文献   
998.
This study investigates the role of risk in farmers' acreage decisions for major field crops in the North Central region by revisiting an earlier study by Chavas and Holt. The empirical model is forward-looking and reflects better variable measurement. We test the effects of wealth and revenue risk on supply response. Estimated results are also used to examine the production impact of counter-cyclical payments (CCPs). We find that the effects of risk on supply response are not strong. An increase in initial wealth would lead to greater crop acreage, consistent with decreasing absolute risk aversion. The effect of CCPs on production appears to be negligible.  相似文献   
999.
1000.
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