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This paper estimates technical efficiency (TE) measures using four alternative production frontier models, and evaluates the sensitivity of the results to the choice of methodology. The Cobb-Douglas functional form along with data for 1982 and 1983 from 404 dairy farms located throughout six northeastern states in the US are used in the estimation. A general conclusion is that, broadly speaking, frontier function models are neutrally upwardly scaled versions of the OLS or average model. A second conclusion is that different models yield markedly different efficiency levels across firms. However, the correlation between the indexes from the various methods is high, which implies that the ordinal ranking of firms according to their measured level of technical efficiency appears to be independent of the method used for a given year. By comparison, the correlation between efficiency indexes for the same method across time, although positive, is much lower than the previous set of correlations. Correlation analysis of efficiency versus farm size and of efficiency versus returns over variable costs, based on the alternative models, yielded consistent results.  相似文献   
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This paper extends the conjectural approach in industrial organisation to the analysis of imperfections in output and factor markets. Starting from the specification of a production function, the econometric analysis is based on the formulation and estimation of a simultaneous-equation model consisting of a production function, first-order conditions associated with factor employment, and two conjectural elasticities to parameterise the industry's oligopoly and oligopsony equilibria. As an example, we provide an application to the US meat-packing industry. Our results suggest that the industry exercises market power in both the output (meat) market and the factor (live animal) market.  相似文献   
94.
This paper is the result of survey investigation the attitudes of Western Canadian farmers toward two biotechonological products, ENFIX-L and PB-50. Farmers were asked to rate both the importance and the performance of 21 attributes of the products. Soil depletion was found to be an important concern to many farmers. personal and environmental risks were less of a concern. Overall, it was found that the non-biotech-nological aspects of a product would prevail in purchasing decisions.  相似文献   
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Increased AIDS mortality and other preexisting conditions have contributed to agricultural productivity declines in the districts of Masaka and Rakai in Uganda. These two districts were the most fertile in Uganda and also had the highest HIV seroprevalence rates in Africa. 66% of study households experienced land use decline to some extent over the past 5 years. The 11% decline in poultry production and 32% decline in cattle production was reportedly due to poor management and loss of grazing land from overpopulation and larger scale farms. The most frequently reported reasons for crop reductions were death and sickness; these was estimated as affecting 8% of families with children under 5 years in the study area. Morbidity and mortality as a reason for the decline was reported two times as much as poverty and decline in international coffee prices. Other reasons for loss of productivity were food shortages and insecurity, loss of income, and reduced ability to respond to educational and medical needs. Cassava is replacing the culturally preferred matooke banana as a crop that is more disease-, pest-, and drought resistant. The banana weevil has been a recent problem. Marginal farming systems have been the most affected by declines in land use and livestock production, but fertile areas have not been spared the impact from AIDS and adult mortality. Poverty has decreased the use of pesticides, herbicides, and fertilizers in the districts. Policy has had an impact on agricultural practices: population growth and inheritance have added to loss of individual land holdings and contributed to fallow periods and infertility. Appropriate land management practices have not been adequately promoted in the agricultural extension service. Civil wars and the drop in coffee prices have reduced the number of farm laborers. Common grazing land has been turned over to large commercial ranches. Government should maintain research and monitoring of declines in food and cash crop production and manpower needs. Policy must be designed to respond to the complicated factors affecting productivity. High AIDS prevalence areas and marginal areas where reduced production effects would be the most severe must be given priority status. Development of cash crop alternatives must be examined and perhaps supported on an experimental basis by donor agencies. Maximum productivity should be encouraged by rural extension and education agencies. A number of other specific recommendations were made for individual survival strategies to maintain high agricultural productivity.  相似文献   
96.
This paper considers input pricing rules for a producer cooperative which supplies its members with two inputs: a publicly provided private input (water), and a local public input (road services). An Israeli Moshav which allocates land equally among producers is a good example. The cooperative uses a two-part pricing rule: a product-dependent uniform fee (head tax) and a user charge per unit of the private input. Discrimination of head tax among the producer groups is shown to dominate that of user charge in the short run. However, land reallocation among producers can result in a Pareto-superior pricing rule and the Henry George theorem emerges in the long run. Thus, allowing land leasing while maintaining equal rights to land increases producer welfare.  相似文献   
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Testing for non-linear dependence in inter-war exchange rates   总被引:1,自引:0,他引:1  
Testing for Non-Linear Dependence in Inter-War Exchange Rates. — This paper tests weekly inter-war floating exchange rate data for the pound-dollar, pound-franc and pound-reichsmark for non-linearity. Initial tests reveal strong evidence of generic non-linearity in these series and indicate neglected non-linear structure in the residuals of linear representations. Attempts to model this structure using GARCH residual processes have only been partially successful. Thus, two parametric models of such non-linearity were estimated. Comparing the forecasts from these models shows the mean square forecast errors of linear-GARCH and bilinear models to be lower than those from linear forecasts for all series, and that SETAR model forecasts outperform all other models for the pound-dollar.  相似文献   
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