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131.
This paper investigates the odds of generating a 100-fold return in the cattle futures market. We employ cattle futures data for the period October 11, 1978, through July 31, 1979, to compute the probability of obtaining such a return. The tests are constructed to give the investor the benefit of the doubt whenever doubt exists. The most conservative finding is that the probability is one in approximately thirty-one trillion. Assuming that the return is made in the most efficient way possible, this probability falls to approximately 1.5×10−16.  相似文献   
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133.
Multinational companies face increasing risks arising from external risk factors, e.g. exchange rates, interest rates and commodity prices, which they have learned to hedge using derivatives. However, despite increasing disclosure requirements, a firm's net risk profile may not be transparent to shareholders. We develop the ‘Component Value‐at‐Risk (VaR)’ framework for companies to identify the multi‐dimensional downside risk profile as perceived by shareholders. This framework allows for decomposing downside risk into components that are attributable to each of the underlying risk factors. The firm can compare this perceived VaR, including its composition and dynamics, to an internal VaR based on net exposures as it is known to the company. Any differences may lead to surprises at times of earnings announcements and thus constitute a litigation threat to the firm. It may reduce this information asymmetry through targeted communication efforts.  相似文献   
134.
Ethical attitudes in relation to meat purchases were studied among urban and rural consumers in Scotland. All subjects perceived at least some ethical issues in relation to animal production systems, in particular, systems keeping animals in close confinement. Welfare‐friendly production systems were viewed as adding value to a food, but this value was not necessarily realizable to producers if purchases occurred only when foods were on special offer. Statements made by individuals were often contradictory, revealing ambivalence, unresolved value conflicts and a general lack of involvement in the nature of meat production. A number of barriers to the establishment of stable attitudes and behaviours in relation to the ethical treatment of food animals were also identified. A key finding of the study is that individuals can hold two views on animal welfare. On the one hand, they may think as citizens influencing societal standards, and on the other, as consumers at the point of purchase. As citizens, they support the notion of animals being entitled to a good life; as meat consumers, they avoid the cognitive connection with the live animal. This paper explores both the citizen–consumer relationship and purchase strategies used by consumers to resolve value conflicts. Lessons for public and commercial policy are highlighted in the context of the Curry Report (2002) which advocates more effective market segmentation where markets are finely attuned to their customers, with the development of a number of assurance schemes discussed in the article.  相似文献   
135.
Statistical Decision Problems and Bayesian Nonparametric Methods   总被引:1,自引:0,他引:1  
This paper considers parametric statistical decision problems conducted within a Bayesian nonparametric context. Our work was motivated by the realisation that typical parametric model selection procedures are essentially incoherent. We argue that one solution to this problem is to use a flexible enough model in the first place, a model that will not be checked no matter what data arrive. Ideally, one would use a nonparametric model to describe all the uncertainty about the density function generating the data. However, parametric models are the preferred choice for many statisticians, despite the incoherence involved in model checking, incoherence that is quite often ignored for pragmatic reasons. In this paper we show how coherent parametric inference can be carried out via decision theory and Bayesian nonparametrics. None of the ingredients discussed here are new, but our main point only becomes evident when one sees all priors—even parametric ones—as measures on sets of densities as opposed to measures on finite-dimensional parameter spaces.  相似文献   
136.
This study explores the impact of environmental turbulence on relationships between personal and organizational characteristics, personal values, ethical perceptions, and behavioral intentions. A causal model is tested using data obtained from a national sample of marketing research professionals in South Africa. The findings suggest turbulent conditions lead professionals to report stronger values and ethical norms, but less ethical behavioral intentions. Implications are drawn for organizations confronting growing turbulence in their external environments. A number of suggestions are made for ongoing research. Michael H. Morris became the Fletcher Jones Chair in Entrepreneurship at the University of the Pacific, Stockton, CA in 1993. He received his Ph.D. in Marketing. He is the author of two books and over forty articles in academic journals, including the Journal of International Business Studies, the Journal of Business Research, the Journal of Management, and the Journal of the Academy of Marketing Science. Dr. Morris' principal research interests include entrepreneurial behavior, industrial marketing strategy, and pricing.Amy Seidel Marks has been a Senior Lecturer in Marketing at the GSB UCT since 1989. She holds a Ph.D. in Marketing from the Kellogg Graduate School of Management, and has worked in the areas of consumer behavior analysis and social marketing for 20 years. During her time in South Africa she has conducted numerous research projects in areas such as AIDS prevention, tobacco control and iodine deficiency, and has also served as a consultant to national projects in tuberculosis drug compliance, tobacco control and adult education.Jeff Allen received his doctorate from the University of Kentucky. He is currently an Assistant Professor of Marketing at the University of Central Florida, Orlando, Florida, Dr. Allen has published in various national and international academic journals on topics of social responsibility, marketing ethics, and health care marketing. Newman S. Perry, Jr. is Professor of Management, School of Business and Public Administration at the University of the Pacific in Stockton California. He has just completed Business, Government, and Society: Managing Competitiveness, Ethics, and Social Issues published by Prentice-Hall and previously coauthored a book on strategic management.  相似文献   
137.
138.
A reformulation of the economic theory of fertility   总被引:9,自引:0,他引:9  
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139.
An overview is provided of the World Bank study about the interaction between rapid population growth, poor agricultural performance, and environmental degradation. The links between these 3 phenomena are identified as traditional methods of crop and livestock production, land tenure systems, women's responsibilities, and methods of forest use. When land was abundant and capital limited, pastoralism, shifting cultivation, and setting aside fallow land was possible. Mobility and allowances for natural regeneration of vegetation could not continue with rapid population growth. Permanent settlements developed but cultivation methods remained the same; the result was deterioration of soil fertility, low yields, and erosion of soil as occurred in Rwanda, Burkina Faso, and parts of Nigeria. Technological innovation has been slow and poor roads have interfered with a market oriented economy. Inappropriate pricing, exchange rates, and fiscal policies also prevent productivity gains. A heavy demand is placed on women's time. Demand for children is high and is stimulated by environmental degradation, food insecurity, land tenure systems, and cultural traditions. Child labor is needed. The demand for contraception is 30-50% in North Africa, 36-55% in Asia, and 40-60% in South America. Land ownership problems have arisen under community ownership and between herders and settlers. Solutions have ranged from land nationalization and arbitrary designation of individual ownership. Open access situations have developed and lent themselves to exploitation. Fuelwood needs have exacerbated the destruction of forests. Commercial logging accounted for 10-20% of the forest loss. New approaches are needed to link cross-sectionally population, the environment, an agriculture. Emphasis should be on resource conservation, family planning, and environmentally benign intensive farming. Agricultural production needs to grow at 4%/year, fertility lowered by 50% over 30 years, and deforestation slowed. Women's time constraints should b alleviated and productivity improved. Open access and state ownership should be stopped.  相似文献   
140.
"A projection model based on a multivariate continuous state, stochastic process is presented. The model allows multiple time-varying covariates to be used so parameters can be estimated from time series information on health changes and mortality, and their interaction. Health changes are simulated by altering parameters controlling the age trajectory and diffusion of risk factor means, variances, and covariances....By increasing the information used in projections it may be possible to better (a) anticipate the state of health at extreme ages, (b) forecast changes in health at specific ages over time, (c) stimulate the effects of specific interventions, and (d) determine the sensitivity of outcomes to a range of interventions."  相似文献   
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