Component efficient solutions in line-graph games with applications

Recently, applications of cooperative game theory to economic allocation problems have gained popularity. We investigate a class of cooperative games that generalizes some economic applications with a similar structure. These are the so-called line-graph games being cooperative TU-games in which the players are linearly ordered. Examples of situations that can be modeled like this are sequencing situations and water distribution problems. We define four properties with respect to deleting edges that each selects a unique component efficient solution on the class of line-graph games. We interpret these solutions and properties in terms of dividend distributions, and apply them to economic situations. This research has been done while the third author was visiting Tinbergen Institute at the Free University, Amsterdam. The research is part of the Research Programme “Strategic and Cooperative Decision Making” at the Department of Econometrics. Financial support from the Netherlands Organization for Scientific Research (NWO) in the framework of the Russian-Dutch programme for scientific cooperation, is gratefully acknowledged. The third author also appreciates partial financial support from the Russian Leading Scientific Schools Fund (grant 80.2003.6) and Russian Humanitarian Scientific Fund (grant 02-02-00189a). We thank three anonymous referees for their valuable comments.     

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.     

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     

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.