Finding Pareto Optimal Insurance Contracts

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.     

THE SQUARED ORNSTEIN-UHLENBECK MARKET

We study a complete market containing J assets, each asset contributing to the production of a single commodity at a rate that is a solution to the squared Ornstein-Uhlenbeck (Cox-Ingersoll-Ross) SDE. The assets are owned by K agents with CRRA utility functions, who follow feasible consumption/investment regimes so as to maximize their expected time-additive utility from consumption. We compute the equilibrium for this economy and determine the state-price density process from market clearing. Reducing to a single (representative) agent, and exploiting the relation between the squared-OU and squared-Bessel SDEs, we obtain closed-form expressions for the values of bonds, assets, and options on the total asset value. Typical model parameters are estimated by fitting bond price data, and we use these parameters to price the assets and options numerically. Implications for the total asset price itself as a diffusion are discussed. We also estimate implied volatility surfaces for options and bond yields.     

工作本位学习理论的系统分析

工作本位学习是基于从学校到工作岗位(school-to-work)的理念下提出来的,试图整合学习策略和工作实践,促进学习者的学习,以更好适应工作的需要。工作本位课程理论是在上述理念基础上开发出来的,对我国高职教育提供有益的启示。     

Urban Influence on Costs of Production in the Corn Belt

This article determines the relative technical efficiency of rural- and urban-influenced crop/livestock enterprises in the Corn Belt. Farmers in urban-influenced locations are less technically efficient than farmers in rural locations. During 1998–2000, stochastic production frontier procedures indicate that a 10% increase in urban influence leads to a close to 4% decrease in technical efficiency. The most successful urban-influenced farms have controlled costs as effectively as rural farms. They have tended to de-emphasize that nondairy livestock activities—particularly beef and hogs—do not rely extensively on off-farm income, and have relatively large, less residential/lifestyle operations compared to less successful urban-influenced farmers. However, our statistical analysis clearly bears out the refrain in popular literature that urban proximity raises the cost for, and decreases the viability of, traditional farms.     

Estimation of Agricultural Production Functfons on a World-Wide Basis

Agricultural production is becoming increasingly capital and research intensive. Hayami and Ruttan, along with others, have developed and applied the metaproduction functional approach to the examination of this phenomenon on a worldwide basis. Limitations to the approach derive from a restrictive functional form chosen for estimation, and from a restrictive specification of agricultural capital and land. This study addresses those difficulties by use of the flexible translog functional form for estimation and by specifying an overall agricultural capital index and a land measure incorporating differences in the quality of land (agricultural natural resource) endowments. Estimation results indicate that agricultural comparative advantage in production is likely shifting to developed countries relative to LDC's due to capital constraints in the latter. Also agricultural potential (i.e., land endowments) do not serve to differentiate nations on the basis of agricultural production. Investment in agriculture, including land improvement, is key to the determination of comparative advantage. La production agricole fait appelle de plus en plus a beaucoup de re-cherches et de capitaux. Hayami et Ruttan, avec d'autres, ont developpe et appliqué l'approche fonctionnelle métaproduction pour examiner ce phénomena à l‘échelle du monde. Les limitations de cette approache provienneent de la forme fonctionnelle restrictive choisie pour l'estimation, et de la spécification restrictive de capitaux et terres agricoles. Cette étude traite ces difficultés en utilisant la formule “translog’ fonctionnelle adaptable pour l'estimation et en spécificant un indice du capital agricole global et une mesure de terre qui incorpore les différences du qualité des terres agricoles (ressources agricoles naturelles). Tous les résultats estimatifs indiquent que l'avantage comparatif agricole de production s'incline vers les pays développés parraport aux PMD dû aux constraintes de capitaux dans ces derniers. Aussi la capacité agricole (c'est à dire la richesse des sols) ne sert pas à différencier les nations sur le plan de production agricole. L'investissement dans l'agriculte, notamment l'amélioration de terre, est la cief pour déterminer l'avantage comparatif.     

论英语教学与学生的非智力因素培养

目前，英语学习中智力和非智力因素是影响学生学业成绩的两个重要因素。人的智力包括注意力、观察力、思维和记忆能力；而非智力是指人的意志、兴趣、动机和情感。本文就教师如何在英语教学中培养学生的非智力因素，促进他们消除学习方法上存在的某些障碍作了一些分析，以便帮助他们提高学习成绩。     

A comparison of several approximations to the power function of the likelihood ratio test in covariance structure analysis*

In this paper we compare alternative asymptotic approximations to the power of the likelihood ratio test used in covariance structure analysis for testing the fit of a model. Alternative expressions for the noncentrality parameter (ncp) lead to different approximations to the power function. It appears that for alternative covariance matrices close to the null hypothesis, the alternative ncp's lead to similar values, while for alternative covariance matrices far from H_o the different expressions for the ncp can conflict substantively. Monte Carlo evidence shows that the ncp proposed in Satorra and Saris (1985) gives the most accurate power approximations.     

多媒体教学在高职高专英语教学中的应用

在高职高专英语教学中运用多媒体可充分调动学生学习的主动性和积极性，培养学生的创新能力，进而优化课堂教学，提高教学效率，有效地解决高职高专英语教学中存在的问题。     

Implementing reverse e-auctions: A learning process

Reverse e-auctions, which enable suppliers to compete on-line in real-time, are changing the way organizations select their suppliers. We explore how five large firms in different industries learned to use e-auctions, and how e-auctions were integrated into their purchasing processes. To successfully implement e-auctions, organizations should: (1) build e-auction competencies; (2) organize for knowledge management; (3) create a holistic sourcing process; (4) focus on the total cost of ownership; and (5) experiment with e-auction designs. Key observations are drawn from the case studies, and implications for supply managers are presented.     

Does success diminish competitive responsiveness? Reconciling conflicting perspectives

Previous research provides conflicting evidence of the association between the past performance of a business and its competitive responsiveness, with researchers observing both positive and negative relationships. To clarify this issue, the authors test a model using survey data from the retailing industry. The model delineates direct and indirect mediated paths through ability to respond, motivation to respond, and awareness of competitors’ actions to show how past performance can have both positive and negative influence on competitive responsiveness. However, the overall impact of past performance of an organization on its competitive responsiveness is positive. The implications of these findings for research, practice, and theory are discussed. Satish Jayachandran (satish@moore.sc.edu) is an assistant professor of marketing in the Moore School of Business at the University of South Carolina. His research interests are focused on issues related to the market responsiveness of firms. His research has been published in theJournal of Marketing and theJournal of the Academy of Marketing Science. He was a recipient of the Harold H. Maynard Award for 2001 from theJournal of Marketing. He was nominated a young scholar by the Marketing Science Institute in 2003. Rajan Varadarajan (varadarajan@tamu.edu) is Distinguished Professor of Marketing and holder of the Ford Chair in marketing and e-commerce at Texas A & M University. His teaching and research interests are in the areas of strategy, international marketing, and e-commerce. His research on these topics has been published in theJournal of Marketing, theJournal of the Academy of Marketing Science, theAcademy of Management Journal, Strategic Management Journal, Sloan Management Review, California Management Review, Business Horizons, theJournal of Business Research, and other journals.