A solution to the random assignment problem on the full preference domain

We consider the problem of allocating a set of indivisible objects to agents in a fair and efficient manner. In a recent paper, Bogomolnaia and Moulin consider the case in which all agents have strict preferences, and propose the probabilistic serial (PS) mechanism; they define a new notion of efficiency, called ordinal efficiency, and prove that the probabilistic serial mechanism finds an envy-free ordinally efficient assignment. However, the restrictive assumption of strict preferences is critical to their algorithm. Our main contribution is an analogous algorithm for the full preference domain in which agents are allowed to be indifferent between objects. Our algorithm is based on a reinterpretation of the PS mechanism as an iterative algorithm to compute a “flow” in an associated network. In addition we show that on the full preference domain it is impossible for even a weak strategyproof mechanism to find a random assignment that is both ordinally efficient and envy-free.     

EDGAR on the internet: The welfare effects of wider information distribution in an experimental market for risky assets

Policies such as the SEC’s Fair Disclosure Rule, and technologies such as SEC EDGAR, aim to disseminate corporate disclosures to a wider audience of investors in risky assets. In this study, we adopt an experimental approach to measure whether this wider disclosure is beneficial to these investors. Price-clearing equilibrium models based on utility maximization and non-revealing and fully-revealing prices predict that in a pure exchange economy, an arbitrary trader would prefer that no investors are informed rather than all are informed; non-revealing theory further predicts that an arbitrary trader would prefer a situation in which all traders are informed rather than half the traders are informed. These predictions can be summarized as “None > All > Half”. A laboratory study was conducted to test these predictions. Where previous studies have largely focused on information dissemination and its effects on equilibrium price and insider profits, we focus instead on traders’ expected utility, as measured by their preferences for markets in which none, half, or all traders are informed. Our experimental result contradicts the prediction and indicates “Half > None > All”, i.e. subjects favor a situation where a random half is informed. The implication is that in addition to testing predictions of price equilibrium, experiments should also be used to verify analytical welfare predictions of expected utility under different policy choices. JEL Classification D82, D53, G14, L86 This work was largely completed while this author was at The Hong Kong University of Science and Technology.     

On transaction efficiency and China’s Urban-Rural disparity

It is recommended for economists to examine China’s Urban-Rural disparity from the perspective of transaction efficiency, in that it can provide us with a systematic explanation to both the cases of different countries and development stages. China’s Urban-Rural disparity is special and virtually a demonstration of its special transaction efficiency structure. Exploration of China’s Urban-Rural disparity from such perspective indicates that, different from those in countries with a market economy, China’s case involves many exogenous and contrived factors. Therefore, the solutions are to improve the whole transaction efficiency in the economy, which includes eliminating its regionally unfavorable policies and institutions, and enforcing more favorable and regionally balanced institutional reforms. __________ Translated from Fudan Journal (复旦学报, Social Science Edition), 2006, (1) (in Chinese)     

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.     

基于效率的长三角区域创新网络形成机理

在分析了长江三角洲区域创新网络的形成基础上,着重探索长三角区域创新网络非同质化实质和三个创新群的外溢效率内在的逻辑关系,从而构建了基于效率长三角区域创新网络形成内在机理的理论研究框架。长三角区域创新网络效率不仅限于“点”与“点”之间的外溢效应,而主要体现于更高层次“群”与“群”之间的外溢效应。     

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     

中国各地区集约经济运营绩效的DEA评价

DEA方法是进行相对有效性评价的一种方法。其最先提出并被广泛应用的C2R模型可同时判断决策单元是否同时满足技术有效和规模有效。通过利用DEA模型对我国30个地区的集约经营效率进行了分析评价,并探讨了制约我国各地区集约经济发展的重要因素及其对策问题。     

越库作业调度问题及其启发式算法研究

主要研究两台机器环境下的以加权完工时间和为目标函数的越库调度问题。首先针对两机器越库调度问题进行研究与分析,给出该问题最优解的若干性质;其次,基于最优解的性质,提出求解该问题的启发式算法,并在此基础上对所给算法进行改进;最后,通过数值实验与动态规划算法比较,证明所给算法及其改进算法的有效性。     

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。