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101.
This article determines the relative technical efficiency of rural- and urban-influenced crop/livestock enterprises in the Corn Belt. Farmers in urban-influenced locations are less technically efficient than farmers in rural locations. During 1998–2000, stochastic production frontier procedures indicate that a 10% increase in urban influence leads to a close to 4% decrease in technical efficiency. The most successful urban-influenced farms have controlled costs as effectively as rural farms. They have tended to de-emphasize that nondairy livestock activities—particularly beef and hogs—do not rely extensively on off-farm income, and have relatively large, less residential/lifestyle operations compared to less successful urban-influenced farmers. However, our statistical analysis clearly bears out the refrain in popular literature that urban proximity raises the cost for, and decreases the viability of, traditional farms.  相似文献   
102.
Education vouchers ore conventionally attacked by commentators who prefer to maintain the dominance of the srate in the supply of education. Richard Henderson, of the stockbrokers Sheppards & Chase, analyses the vulnerability of vouchers to capture by pressure group and therefore argues for a genuine market in education without the compromise of vouchers.  相似文献   
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In this paper we investigate the use of the structured full rank model for hedging the balance sheet of a financial institution. Simulation results suggest that the optimal hedge is insensitive to changes in parameter estimates. In addition, we hedge a portfolio of Treasury bills using both the full information covariance matrix and the structured covariance matrix. We then contrast these results with those obtained from a duration-based model. Empirical results suggest that the structured full rank model is generally more effective in hedging applications than either the full information model or duration-based model.  相似文献   
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The maritime industry provides an interesting case study of the design and implementation of drug-testing programs in the transportation industry during the 1980s. It is clear that such programs were designed and implemented less because of empirical evidence of safety problems than for political reasons. The results in the maritime industry are indicative of a program that is expensive to operate, intrusive with regard to employee privacy, and which will have little or no impact on safety. Focusing such programs on the issue of impairment rather than on the issue of drug usage per se is likely to improve the outcome of the programs. Although, despite common belief, there is little evidence that drug usage or the “drug problem” in U.S. society as a whole had gotten worse in the preceding years (Schonsheck, 1989, 250–251).  相似文献   
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Too often companies fall into a trap when developing a list of performance specifications for a new product. Milton Rosenau calls this the best-of-the-best specification trap. The problem arises whenever a company bases a specification on the combination of the best single features observed in available competitive products. When this happens, the new product's design is driven by competition and is not derived from a unique market insight. This may not provide the basis for a sustainable advantage. Sometimes, rumors of competitive improvements may even lead to sudden changes in the specification, creating delays in the development process. A far better goal is to develop a specification that responds to an unrecognized and unfilled user need, one that adds high value to users. His points are illustrated with several examples.  相似文献   
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The use of transferable discharge permits as a water pollution control policy is rapidly increasing in the United States. Drawing on evidence from existing water quality trading programs, this paper provides a taxonomy of the forms that such markets take. Four main structures are identified: exchanges, bilateral negotiations, clearinghouses, and sole-source offsets. Each of these structures has its own strengths and weaknesses; none is optimal for all scenarios. Since market structure is largely determined by a program's rules, policy makers should be aware of the differences between these structures and the conditions under which each comes to be.  相似文献   
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