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71.
When the indemnity schedule is contingent on the farmer's price and individual yield, an optimal crop revenue insurance contract depends only on the farmer's gross revenue. However, this design is not efficient if, as is the case with available contracts, the coverage function is based on imperfect estimators of individual yield and/or price. The producer's degree of prudence and the extent of basis risks have important influences on the optimal indemnity schedule. In this broader context, optimal protection is not provided by available U.S. crop insurance contracts and may include combinations of revenue insurance, yield insurance, futures, and options contracts. 相似文献
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Abstract. We use tax‐based longitudinal microdata for 1982–99 to (i) examine how earnings distributions have shifted, (ii) identify changes in earnings mobility patterns, and (iii) replicate and update Beaudry and Green's cohort analysis of age‐earnings profiles. We find: (i) increased polarization of men's earnings and marked decline in real earnings of workers aged 20–4; (ii) general decline in men's earnings mobility, while women's mobility has increased for young and prime‐age workers; and (iii) upward drift in earnings profiles of 1960s–1970s entry cohorts and downward shifts for 1980s–1990s cohorts (largely confirming Beaudry and Green's findings), but suggestive of steepening profiles for the 1990s cohorts. JEL classification code : J31,O33 相似文献
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Using Turkish industry-level data from 1983 to 1990, we find that politically organized industries receive both higher protection and promotion than unorganized ones. Tariff rates are decreasing (increasing) in the import-penetration ratio and the absolute value of the import-demandelasticity for organized (unorganized) industries. Subsidy rates are decreasing (increasing) in the output-supply elasticity for organized (unorganized) industries. The results are consistent with the predictions of the Grossman–Helpman model and its extension in this paper. The mix of protection and promotion is inversely related to the ratio of their respective marginal deadweight cost measures. 相似文献
78.
This paper deals with on-line computation—or step-wise learning—of Pareto optimal insurance contracts. Our approach tolerates that the loss distribution might be unknown, intractable, or not well specified. Thus we accommodate fairly inexperienced parties. Losses are here simulated or observed, one at a time, and they cause iterated revisions of the premium. The mechanical and global nature of probability calculus thereby yields to more tentative, myopic procedures, possibly closer to how humans operate or reason in face of risk. Sequential revisions may also reduce the expense of insurers' time and money in seeking sufficient statistics. Emphasized below is the remarkable simplicity and stability of the resulting adaptive procedures. Special attention goes to catastrophic risks, and to subsidized or competitive insurance. 相似文献
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The emerging concern about software piracy and illegal or unauthorized use of information technology and software has been
evident in the media and open literature for the last few years. In the course of conducting their academic assignments, the
authors began to compare observations from classroom experiences related to ethics in the use of software and information
technology and systems. Qualitatively and anecdotally, it appeared that many if not most, students had misconceptions about
what represented ethical and unethical behaviors in these realms. Clearly, one can argue that if college students are uncertain
about what constitutes appropriate and inappropriate behavior then this uncertainty will be carried forward into their workplaces
upon graduation. Furthermore, if their workplaces don't provide ethics training as a component of a new employee orientation
program, one can project a potential for unintentional violations and infringements of copyrights and law in the field. This
study was conducted among graduate and undergraduate students to gain insight into their attitudes, perceptions and understanding
of some of the relevant ethics issues. A questionnaire of 11 statements was employed that described ubiquitous but most likely
unethical (or surely dubious) behaviors in the prevailing business and academic environments. Each respondent was asked to
evaluate each statement twice (once for “self” and once for “colleague”) on a five-option highly ethical (5) to neutral (3)
to highly unethical (1) scale. The statements were worded such that lower instrument score was associated with higher ethical
responses. The questionnaire's two-part structure was designed to solicit honest answers. The encouraging learning from this
study was that the overall sample and its various sub-samples did not consider any of the eleven behaviors to be “ethical”
or “highly ethical.” It was also encouraging to note that the overall sample and all sub-samples considered “highly unethical”
those behaviors associated with personal privacy or property or outright theft. This indicated that moral judgment and probity
prevail. The discouraging learning was that behaviors associated with the use of enterprise property were viewed as “neutral”
i.e., neither “ethical” nor “unethical.” These findings suggested confusion and lack of clarity and definition around workplace
deportment as it regards ethics in software and information technology use. The current study suggests that additional research
needs to be conducted to define and clarify the issues, which in turn can form the basis for programs to rectify or at least
ameliorate the situation. 相似文献