三峡库区发展高效生态农业的途径和对策

论述高效生态农业在三峡库区建设和移民安置中的战略意义。从三峡库区实际出发，分析库区高效生态农业发展的现状和难点、机遇和方向。指出高效生态农业的发展不仅能给库区移民带来显著的经济效益，促进库区农业、环境、社会的持续发展，而且能确保三峡工程建设顺利进行和长治久安。并针对目前库区农业存在的问题，提出了库区农业高效生态化及产业化的发展对策。     

Art as an investment: Short and long-term comovements in major painting markets

This paper examines the short and long-term price linkages among major art and equity markets over the period 1976–2001. The art markets examined are Contemporary Masters, French Impressionists, Modern European, 19^th Century European, Old Masters, Surrealists, 20^th Century English and Modern US paintings. A global equity index (with dividends and capitalisation changes) is also included. Multivariate cointegration procedures, Granger non-causality tests, level VAR and generalised variance decomposition analyses based on error-correction and vector autoregressive models are conducted to analyse short and long-run relationships among these markets. The results indicate that there is a stationary long-run relationship and significant short and long run causal linkages between the various painting markets and between the equity market and painting markets. However, in terms of the percentage of variance explained most painting markets are relatively isolated, and other painting markets are generally more important than the equity market in explaining the variance that is not caused by innovations in the market itself. This suggests that opportunities for portfolio diversification in art works alone and in conjunction with equity markets exist, though in common with the literature in this area the study finds that the returns on paintings are much lower and the risks much higher than in conventional financial markets.The authors would like to thank delegates to the 14th Australasian Finance and Banking Conference, University of New South Wales, seminar participants at the Queensland University of Technology and Massey University, Masaki Katsuura, and two anonymous referees for helpful comments on earlier versions of this paper. The financial assistance of a Queensland University of Technology, Faculty of Business Research Initiative Grant is also gratefully acknowledged.     

Using data envelopment analysis approach to estimate the health production efficiencies in China

By using Data Envelopment Analysis approach, we treat the health production system in a certain province as a Decision Making Unit (DMU), identify its inputs and outputs, evaluate its technical efficiency in 1982, 1990 and 2000 respectively, and further analyze the relationship between efficiency scores and social-environmental variables. This paper has found several interesting findings. Firstly, provinces on frontier in different year are different, but provinces far from the frontier keep unchanged. The average efficiency of health production has made a significant progress from 1982 to 2000. Secondly, all provinces in China can be divided into six categories in terms of health production outcome and efficiency, and each category has specific approach of improving health production efficiency. Thirdly, significant differences in health production efficiencies have been found among the eastern, middle and western regions in China, and among the eastern and middle regions. At last, there is significant positive relationship between population density and health production efficiency but negative relationship (not very significant) between the proportions of public health expenditure in total expense and efficiency. Maybe it is the result of inappropriate tendency of public expenditure. The relationship between abilities to pay for health care services and efficiency in urban areas is opposite to that in rural areas. One possible reason is the totally different income and public services treatments between rural and urban residents. Therefore, it is necessary to adjust health policies and service provisions which are specifically designed to different population groups. __________ Translated from Jingji Yanjiu 经济研究 (Economic Research Journal), 2006, (7): 92–105     

农业产业化经营中利益相关者关系、目标选择与实现方式

本文指出,农业产业化经营的利益相关者是农业价值创造和价值实现的重要影响因素,正确处理好利益相关者关系,有利于保障和提升农业利益,有利于农业价值创造与农业价值实现,这包括农户与龙头企业、政府、中介组织、合作经济组织以及龙头企业与协会之间的关系。农业产业化经营要以产业运作过程商品化、利益分配合理化等方式,实现农业价值创造最大化和农业价值分配最优化的农业产业化目标。     

多元化战略在中国旅游企业中的实施效率分析

文章对我国旅游企业的多元化战略管理进行了调查分析,从中总结出旅游企业的多元化战略实施的效率与非效率性的原因。     

Testing equality of variances in the analysis of repeated measurements

The problem of comparing the precisions of two instruments using repeated measurements can be cast as an extension of the Pitman-Morgan problem of testing equality of variances of a bivariate normal distribution. Hawkins (1981) decomposes the hypothesis of equal variances in this model into two subhypotheses for which simple tests exist. For the overall hypothesis he proposes to combine the tests of the subhypotheses using Fisher's method and empirically compares the component tests and their combination with the likelihood ratio test. In this paper an attempt is made to resolve some discrepancies and puzzling conclusions in Hawkins's study and to propose simple modifications.
The new tests are compared to the tests discussed by Hawkins and to each other both in terms of the finite sample power (estimated by Monte Carlo simulation) and theoretically in terms of asymptotic relative efficiencies.     

ML– and semiparametric estimation in logistic models with incomplete covariate data

ML–estimation of regression parameters with incomplete covariate information usually requires a distributional assumption regarding the concerned covariates that implies a source of misspecification. Semiparametric procedures avoid such assumptions at the expense of efficiency. In this paper a simulation study with small sample size is carried out to get an idea of the performance of the ML–estimator under misspecification and to compare it with the semiparametric procedures when the former is based on a correct assumption. The results show that there is only a little gain by correct parametric assumptions, which does not justify the possibly large bias when the assumptions are not met. Additionally, a simple modification of the complete case estimator appears to be nearly semiparametric efficient.     

基于微粒群优化算法的物流配送中心选址问题研究

结合物流配送中心选址的特点，建立数学模型．在此基础上研究了基于微粒群算法的物流多配送中心选址问题，得到一种新的多配送中心选址方法。仿真结果证明此方法比传统选址方法更适合多配送中心选址和非线性问题的优化，并且具有传统算法所不具备的灵活性，适用多样的物流配送模型。     

金融制度缺陷:我国农村金融效率低下的根源

本文通过统计数据对我国农村金融资源配置效率的分析表明,我国农村金融资源配置效率相对低下.造成农村金融资源配置效率低下的原因,是现阶段农村金融制度的有效供给不足,导致了金融资源配置无法满足帕累托条件.因此,提高农村金融资源配置效率的关键,在于农村金融制度的创新和有效供给.     

How efficient are national environmental standards? A benefit-cost analysis of the United States experience

This paper summarizes the results of the first systematic, geographically-specific efficiency assessment of the U.S. experience with national environmental standards and with alternative approaches to establishing those standards. This ex-post evaluation assessed the net benefits that resulted from EPA's regulation of conventional air and water pollutants from the pulp and paper industry between 1973 and 1984. The paper compares the benefit-cost efficiencies of the three dominant regulatory approaches: technology, ambient, and benefits. Unlike previous studies, which assessed benefits and costs on a national basis, the study estimates both costs and benefits on a facility-by-facility basis. The analysis shows how the efficiency of national environmental regulations can vary dramatically at local levels. The authors conclude that the technology-based standards for water pollution management failed as an efficient environmental strategy. The costs clearly exceeded the benefits in the aggregate, as well as in the specific in most situations. Benefits exceeded costs at only 11 of the 68 mills investigated. The ambient based standards for air pollution management succeeded as an environmental strategy in the aggregate, but succeeded in the specific for only one-third of the mills (22 of 60 mills). The benefits-based standards for air pollution management also succeeded in the aggregate as well as in the specific for about one-half of the mills. Benefits exceeded costs at 29 of the 60 mills investigated. The results of the study point to two major conclusions. First, a regulatory policy that is based on some measure of environmental results, either ambient-based or benefits-based, will be more efficient than a policy that ignores environmental results. Second, truly efficient policies for reducing environmental risks require pollution mitigation decisions that take into account local conditions. These include not only the changes in local ambient conditions, but also the number of people who will benefit from pollution reduction decisions. This latter conclusion suggests that national environmental standards per se may be inefficient.Dr. Luken is currently Senior Environmental Advisor to the United Nations Industrial Development Organization (UNIDO) in Vienna, Austria. He is on leave from the U.S. EPA where he was Chief of the Economic Analysis and Research Branch of the Office of Policy, Planning and Evaluation (OPPE). Mr. Clark is President of Environmental Economics Associates of Traverse City, Michigan. He was formerly Chief of EPA's Cost and Economic Impact Analysis Branch in OPPE. The views expressed are those of the authors and do not represent the views of the U.S. Environmental Protection Agency.