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This article reports on a study of the impact of risk on farm management practices in northern Syria, focusing particularly on how these are affected by risk aversion and farm size. The study is based on production data from an eight-year field trial and on prices from market surveys. A large linear programming model is built, representing the eight years as observations from a discrete probability distribution. Risk aversion is modelled by inclusion of a utility function with constant relative risk aversion, represented using the DEMP/UEP approach.  相似文献   
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In this note the supply responses in maize and wheat production are estimated from distributed lag models. The Nerlove model and the Fisher distributed lag model fit Kenyan data but more complicated models, like the polynomial lag model, do not. The calculated price elasticities suggest that Kenyan large-scale farmers are highly responsive to price changes. Some policy implications are drawn from the analysis.  相似文献   
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Conclusion The purpose of this study is to reduce information costs in the market for graduate education in economics and the market for Ph.D. economists by providing information on research concentration in each of 19 fields for 1980–1986. Some variation in publishing performance across fields is found in highly regarded universities. Unexpected faculty strength is discovered in some middle level departments for particular fields. Among middle- and lower-ranked departments, substantial publishing diversity across fields is evident.  相似文献   
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There is an increasing realization, world‐wide and in Southern Africa, that conservation and development are compatible.

Because human communities in the less developed rural areas are dependent on a renewable group of resources, including soil, water and forests, it is imperative that land use systems that protect these resources are introduced.

The predominance of subsistence agriculture in these areas is the most difficult syndrome of under‐development. An overall rural development strategy is required that integrates human development with resources management Where the population carrying capacity of the land has already been exceeded, a process of rapid villagization/urbanization is required. Village/urban growth and agricultural development require a carefully co‐ordinated programme of land capability analysis and planning, as well as active investment in infrastructure and the introduction of appropriate technologies and institutions.  相似文献   

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