Efficiency outcomes of market concentration and managed care

The paper examines how hospital cost efficiency has reacted to extensive horizontal integrations of hospitals and rapid growth of managed care in the US health care industry. Cost efficiency is estimated by using panel data approaches to relax the assumptions for the hospital effects imposed in earlier studies. The paper shows that higher managed care penetration over time is associated with greater hospital efficiency, and higher market concentration is positively associated with efficiency when markets are highly competitive or highly concentrated.     

Nonparametric estimation of distribution functions

Summary Using Silverman and Young’s (1987) idea of rescaling a rescaled smoothed empirical distribution function is defined and investigated when the smoothing parameter depends on the data. The rescaled smoothed estimator is shown to be often better than the commonly used ordinary smoothed estimator.     

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.     

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.     

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.     

强化企事业单位内部审计的研究

随着企事业单位管理的需要,内部审计显得越来越重要。本文通过阐述我国企业内部审计中存在的问题,从内部审计认识、内部审计建设、内部审计人员三个方面进行分析,从中找出对策。     

论高校图书馆的信息素质教育职能

信息时代的来临使信息素质成为人才综合能力的重要标志。面对信息浪潮的挑战 ,高校图书馆应充分认识到信息素质教育的重要性与自身优势 ,研究开展信息素质教育的方法 ,充分发挥信息素质教育的职能 ,义不容辞地承担起信息素质教育的重任     

Environmental protection versus economic growth

This paper presents and analyses the differences in the eco-models implemented worldwide （such as whether and how carbon taxes being ＂recycled＂）, or in their efficiency parameters （inconsistent parameter values that account for different results）. This is the assumption that a real tradeoff exists between the production of environmental goods. The present article empirically proves that something must be given up in order to gain something else, and once equations are specified to trace out the path of the economy over time, the natural economic formulation of such equations will embody the notion of economic and bio-tradeoffs.     

Make One——基于软件功能构件的通用电子设备模式研究

首先，指出并分析了基于传统的系统体系结构模式而设计的信息设备与其应用功能之间存在整体堆积性和时空不变性的优缺点；然后，根据先进的信息产品应用功能软件化、构件化的思想，提出一种新的设备与应用功能可互相分离、应用功能构件可重载的Make One设备模式，讨论了Make One模式设备的功能结构特点；进而，给出了一个Make One设备模型的嵌入式容器－构件实现方案；最后，探讨了在互联网环境下Make One模式的应用服务体系。