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51.
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When assessing farming strategies, it is important to account for the opportunities provided for tactically adjusting to outcomes of risk. The hypothesis that accounting for tactical adjustment is more important than accounting for risk attitude was supported in this study with regard to identifying the optimal drainage recirculation strategy for an irrigated dairy farm. Failing to account for tactical adjustment would lead to a sub-optimal choice, costing the farmer about A$3 100 in present value terms. In contrast, failing to account for risk aversion would not affect the strategy chosen. The distribution method was found to be well suited to modelling tactical adjustment.  相似文献   
53.
We use a vertical product differentiation model under partial market coverage to study the social welfare optimum and duopoly equilibrium when convex costs of quality provision are either fixed or variable in terms of production. We show the following new results. First, under fixed costs, the social planner charges a uniform price for the single variant that just covers costs of quality provision. Like the duopoly equilibrium, this socially optimal pricing entails a partially uncovered market, but a smaller share of the market is served compared with the duopoly equilibrium. Second, for the variable cost case, it is socially optimal to provide both high‐ and low‐quality variants, but market shares need not be equal. This differs from the result in fully covered markets. Third, in the duopoly equilibrium, the quality spread is too wide under variable costs relative to the social optimum. Under fixed costs, the duopoly produces two variants, but quality is too low relative to the social optimum, which has only one variant.  相似文献   
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S. K. Bar-Lev  D. Plachky 《Metrika》1989,36(1):331-336
Summary Completeness of a family of probability distributions implies its bounded completeness but not conversely. An example of a family which is boundedly complete but not complete was presented by Lehmann and Scheffe [5]. This appears to be the only such example quoted in the statistical literature. The purpose of this note is to provide further examples of this type. It is shown that any given family of power series distributions can be used to construct a class containing infinitely many boundedly complete, but not complete, families. Furthermore, it is shown that the family of continuous distributions , is boundedly complete, but not complete, whereU denotes the uniform distribution on [a, b] and {P ϑ,ϑ ∈ IR}, is a translation family generated by a distributionP 0 with mean value zero, which is continuous with respect to the Lebesgue measure.  相似文献   
56.
The critical state of the hospital industry, as previously described, generates a difficult decision environment for the materiel manager and those in the purchasing function. The unique life- and death circumstances of hospitals impose a further onus on those who manage them. In the name of saving lives, they can find a convenient excuse to disregard all moral principles, forgetting the Socratic dictum "it is not enough that one lives, but that one lives well." Without the moral "right stuff," they can easily give in to the seductions of momentary gains and glory through ethical short-cuts. There is wisdom and consolation in the words that "nice guys may appear to finish last, but usually they're running in a different race." Studies have established a direct relationship between corporate excellence and ethical values. The reality of competition in the hospital industry dictates that the integration of ethics into the life of the organization should happen by design and not by accident. This is what is meant by strategy. If hospitals would strive for excellence to survive and grow, they should have a strategy with a mission statement that also embodies its moral values and moral agenda. Such an approach does not guarantee that an organization will become immune to moral contamination, but it does provide an antidote.  相似文献   
57.
The South African research community which undertakes all research activity in the social and natural sciences, with and without state and corporate sponsorship, draws its membership mainly from the dominant social group. In this country, the dominant group is both economically and racially determined. Consequently, the white minority dominates the research community and intellectual discourse as it does other socio‐economic and political spheres of society. This situation guarantees the constant reproduction and perpetuation of the social relations of racial domination.

As an agent that generates knowledge and new ideas, research as an academic and intellectual tool of enquiry is an instrument of social control, producing new concepts, language and theoretical abstractions which are not accessible to those outside its multi‐farious disciplines. Insofar as the largest proportion of practitioners of these specialised disciplines is drawn from the dominant group, research has itself become a pivotal part of the dominant ideology. Its role is inevitably and inextricably bound up with the processes of systematic reproduction of the relations of domination.

The aim of this viewpoint is therefore to explore various ways in which research bodies and intellectual discourse in general in South Africa can be deracialised and be made more representative of the social make‐up of society.  相似文献   

58.
Richman LS 《Fortune》1992,126(3):34-40
Many more than ever face the crises of childhood: violence, drugs, bad schools, poverty, divorce, or two parents at work. And no one seems to care.  相似文献   
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