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41.
The Amazon is the largest tropical forest area on Earth, and has been undergoing rapid deforestation for the last four decades. In the Brazilian Amazon, large‐scale pasture for cattle ranching and soybean production are the main land uses, leading to a yearly deforestation rate of 0.5%. These conversions are mostly located in frontier areas distributed along the so‐called “arc of deforestation”. Within this large zone, various land use change processes are interacting through several modes of land valuation and organisation. From several case studies in the State of Pará (Brazil), the current project aims at analysing how landscape dynamics are related to infrastructure development, ecological conditions, zoning policies and to the evolution and the organisation of the production, consumption and marketing chains of livestock products. This paper presents the results for one test site, the region of São Félix do Xingú, South of Pará This region is the focus of land speculation, cattle expansion, and deforestation. Road construction, investments in electrical energy, financial credit for cattle, and the land reform policies have all fuelled this process. All these factors make this region one of the most dynamic agricultural frontiers in the Brazilian Amazon. The main objective of the paper is to improve our understanding of deforestation processes by crossing spatial analyses and 1ivestock economics.studies, and to characterise the role and impact of various natural and anthropic factors in the location and development of the main types of farmers, and their policy implications.  相似文献   
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This article reports on the latest in a series of international comparisons of management practices and performance outcomes of industries in various countries. Here, it is the service industries in the UK and the US which come under the microscope. Among the companies surveyed, there were more world-class performers in the US than the UK, but also more low performers. The concluding part of the article is diagnostic – the authors also suggest measures which could improve performance.  相似文献   
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This study investigates ethical decision-making by considering the differences in ethical judgments between undergraduate business and MBA students on selected ethical issues facing employees and managers of today's businesses. The study further investigates differences in ethical judgments between undergraduates and MBAs in terms of a perceived position as an employee or as a manager. The findings indicate that undergraduate students tend to be more ethical than MBA students and that both groups tend to be more ethical when they perceive themselves as managers rather than employees. The authors discuss the implications for both business practitioners and educators.Shohreh A. Kaynama is Associate Professor of Marketing in the School of Business and Economics at Towson State University in Baltimore, Maryland. She earned a Ph.D. in Marketing and the Decision Sciences. Dr. Kaynama has published extensively in numerous National and International proceedings. Her area of research is strategic marketing, consumer behavior, applications of computers and decision sciences in marketing and global marketing. Louise W. Smith is Professor of Marketing in the School of Business and Economics at Towson State University in Baltimore, Maryland. Dr. Smith's main professional interest is consumer behavior. Dr. Smith's articles have appeared in the Journal of Public Policy & Marketing, Journal of Health Care Marketing, Journal of Marketing Education, Journal of Services Marketing, and Journal of Consumer Marketing among others. Algin B. King is Professor of Marketing in the School of Business and Economics at Towson State University in Baltimore, Maryland. He has served on the Faculties of seven universities, publishing numerous articles in National Professional Meetings Proceedings and scholarly journals including Journal of Euro-Marketing, Atlantic Economic Journal. In addition he has served as a business consultant to numerous business firms.  相似文献   
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The price movements of certain assets can be modeled by stochastic processes that combine continuous diffusion with discrete jumps. This paper compares values of options on assets with no jumps, jumps of fixed size, and jumps drawn from a lognormal distribution. It is shown that not only the magnitude but also the direction of the mispricing of the Black-Scholes model relative to jump models can vary with the distribution family of the jump component. This paper also discusses a methodology for the numerical valuation, via a backward induction algorithm, of American options on a jump-diffusion asset whose early exercise may be profitable. These cannot, in general, be accurately priced using analytic models. The procedure has the further advantage of being easily adaptable to nonanalytic, empirical distributions of period returns and to nonstationarity in the underlying diffusion process.  相似文献   
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This study investigates the relative roles of bond ratings and financial information in the setting of bond yields. Structural equation modeling techniques are used to learn whether ratings determine yields or whether both ratings and yields are determined by a concurrent set of economic and financial factors. Tests of alternative structural model configurations provide evidence regarding the associations between bond ratings, financial information, and bond yields. Both ratings and financial information are found to play an important role in determining bond yields. In addition, yields are consistent with the higher rating in cases of split ratings.  相似文献   
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Optimal investment rules are developed for a producer agency investing in domestic-market generic advertising, export market promotion, and cost-of-production-reducing research. These rules are derived assuming either maximization of producers' surplus or social surplus. The form of the optimality rules differs according to which objective is pursued. Fixed producer agency budgets are also allowed by incorporating a constraint limiting total expenditure on the three activities. Addition of such a constraint substantially alters the structure of the optimal investment rules. Differences in these rules highlight the importance of accounting for the financing mechanism when modeling optimal checkoff fund investment decisions. Optimality rules are simulated using data for the Canadian beef sector. Results suggest historic underinvestment in domestic-market generic advertising but overinvestment in export market promotion. Sensitivity of simulation results underscores the difficulty in assessing optimality of historic producer investment in cost-of-production-reducing research.  相似文献   
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