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71.
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   
72.
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   
73.
Tracking programs have been criticized on the grounds that they harm disadvantaged children. The bulk of empirical research supports this view, but existing studies compare outcomes across students placed in different tracks. Track placement is likely to be endogenous with respect to student outcomes. We use a new strategy for overcoming the endogeneity of track placement and find no evidence that tracking hurts low-ability children. Previous studies have also been based on the assumption that students' enrollment decisions are unrelated to whether or not the school tracks. When we account for the possibility that tracking programs affect school choice, we find evidence that they may help low-ability children.  相似文献   
74.
75.
Elicitation using multiple price list formats   总被引:2,自引:0,他引:2  
We examine the properties of a popular method for eliciting choices and values from experimental subjects, the multiple price list format. The main advantage of this format is that it is relatively transparent to subjects and provides simple incentives for truthful revelation. The main disadvantages are that it only elicits interval responses, and could be susceptible to framing effects. We consider extensions to address and evaluate these concerns. We conclude that although there are framing effects, they can be controlled for with a design that allows for them. We also find that the elicitation of risk attitudes is sensitive to procedures, subject pools, and the format of the multiple price list table, but that the qualitative findings that participants are generally risk averse is robust. The elicitation of discount rates appear less sensitive to details of the experimental design. Electronic Supplementary Material Supplementary material is available in the online version of this article at . JEL Classification C9, D81, D91 An erratum to this article is available at .  相似文献   
76.
Summary. This research studies the role of multivariate distribution structures on random asset returns in determining the optimal allocation vector for an expected utility maximizer. All our conclusions pertain for the set of risk averters. By carefully disturbing symmetry in the distribution of the, possibly covarying, returns, we ascertain the ordinal structure of the optimized allocation vector. Rank order of allocations is also established when a permutation symmetric random vector is mapped into the returns vector through location and scale shifts. It is shown that increased dispersion in the vectors of location and scale parameters benefit, ex-ante, investors as does a decrease in the rank correlation coefficient between the location and scale parameter vectors. Revealed preference comparative static results are identified for the location and scale vectors of asset returns. For most issues addressed, we arrive at much stronger inferences when a safe asset is available. Received: August 8, 2000; revised version: January 8, 2001  相似文献   
77.
78.
Beef cattle producers were surveyed in Texas and Nebraska to investigate perceptions of sources of risk, the effectiveness of risk management strategies, and interest in further risk management education, particularly production risk, using probit analysis. Important decision variables identified are age, prior use of risk management tools, previous attendances of risk management education, and risk aversion. Severe drought and cattle price variability are identified as primary risk factors with potential to affect farm income. Extremely cold weather and disease are of less importance. Understocking pasture and storing hay are perceived most effective as risk management options.  相似文献   
79.
Monopoly, competition and information acquisition   总被引:1,自引:0,他引:1  
An incumbent monopolist is uncertain about its linear demand, but can acquire public information at a cost. We determine how an entry threat affects the firm's information acquisition. If returns to scale are constant and the state-contingent demands become more dispersed as output increases, then entry reduces information acquisition. If, however, either the incumbent or entrant has increasing returns; or if the state-contingent demands are nonlinear or fail increasing dispersion, then entry can increase information. Finally, entry can hurt consumers. Although entry always increases output, it can decrease information. Consumers sometimes prefer a better informed monopoly to a duopoly.  相似文献   
80.
A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers. A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between SCC and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.  相似文献   
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