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21.
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   
22.
Cross-sectional and time-series tests using mimicking portfolios are used to assess the exactness of the APT with(out) a residual market factor. The first factor seems to be sufficient to span the efficient set, whether the model is estimated using (un)conditional variance-covariance matrices that are (un)adjusted for nonsynchronous trading. Although the conditional standard deviations of the mimicking portfolios significantly explain the time-variability of security volatilities, the residuals of the mean equation still exhibit heteroskedasticity. Similar results are obtained for portfolios of CAPM-betaranked securities, and for randomly selected individual securities.  相似文献   
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Cash settlement of derivative contracts makes them susceptible to manipulation by traders who expect to close large positions upon final settlement. Cash settlement also increases underlying volatility when hedgers unwind their hedges if they have no incentives to control their trading costs. Limits on the positions that traders can carry into final settlement can be used to mitigate associated economic inefficiencies when surveillance is insufficient. This article develops a model that regulators can use to set these limits that is based upon microstructure theory. The empirical findings indicate that existing position limits are largely inconsistent with those suggested by the model. © 2005 Wiley Periodicals, Inc. Jrl Fut Mark 25:945–965, 2005  相似文献   
25.
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   
26.
Through the development and extension of theories and scholars’ subsequent empirical analyses of significant, theoretically grounded research questions, the knowledge about corporate entrepreneurship (CE) and its successful use continues to advance. Moreover, the literature suggests important relationships between the corporate environment, managers’ entrepreneurial behavior and successful implementation of corporate entrepreneurship actions. In an attempt to test some of those relationships, we describe an empirical study of 523 managers that examines the relationships among the antecedents to managers’ entrepreneurial behavior, a decision to implement entrepreneurial actions, and resulting job satisfaction and reinforcement practices.  相似文献   
27.
We examine the performance of a metric entropy statistic as a robust test for time-reversibility (TR), symmetry, and serial dependence. It also serves as a measure of goodness-of-fit. The statistic provides a consistent and unified basis in model search, and is a powerful diagnostic measure with surprising ability to pinpoint areas of model failure. We provide empirical evidence comparing the performance of the proposed procedure with some of the modern competitors in nonlinear time-series analysis, such as robust implementations of the BDS and characteristic function-based tests of TR, along with correlation-based competitors such as the Ljung–Box Q-statistic. Unlike our procedure, each of its competitors is motivated for a different, specific, context and hypothesis. Our evidence is based on Monte Carlo simulations along with an application to several stock indices for the US equity market.  相似文献   
28.
Airports in the US air transport network have become increasingly congested, leading to delays for business travelers and freight shipments. Since disruptions in one part of the network exacerbate problems throughout the system, airport infrastructure expansions to enhance air traffic flows confer travel-time savings and reliability benefits, and thus increased worker productivity and shipping efficiency for manufacturing firms. We evaluate such spillovers, and find that higher own-state airport infrastructure implies lower manufacturing costs from both labor- and materials-savings. Airport expansion in connected states has a comparable effect for states with hub airports, and an even greater impact for other states.  相似文献   
29.
This study examined the influence of organization structure on the relationship between top management's entrepreneurial orientation and financial performance. Moderated regression analysis was used to analyse data collected from 80 business organizations. the findings suggest that an entrepreneurial top management style has a positive effect on the performance of organically-structured firms and a negative effect on the performance of mechanistically-structured firms.  相似文献   
30.
The simulation problem is one of the most commonly used formats in computer-assisted instruction (CAI). In medical education, a patient simulation problem is known as a patient management problem (PMP). A number of computerized PMP systems are currently available. However, to date, there is no record of PMP systems having been developed using artificial intelligence. This is noteworthy since artificial intelligence techniques could help in the generation of more effective and intelligent instructional systems.

This paper analyzes and evaluates existing instructional simulation software in clinical medicine in terms of effective educational design attributes. Components of effective PMP systems thus identified are incorporated into a computerized instructional system which uses artificial intelligence techniques for teaching problem-solving and diagnostic skills to undergraduate medical students.  相似文献   

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