基尼系数的含义及其不足

本文提出了用基尼系数作为衡量贫富差距的指标以及基尼系数的各种计算方法。同时指出本身的不足与统计上的难度。并认为在当今中国经济高速发展与贫富差距日益扩大的情况下，有必要不断完善这一指标体系，为政府的宏观决策提供有力的准确与科学的依据。     

On the informational content of advice: a theoretical and experimental study

This paper examines the market for advice and the underlying perception that advice is useful and informative. We do this by first providing a theoretical examination of the informational content of advice and then by setting up a series of experimental markets where this advice is sold. In these markets we provide bidders with a demographic profile of the “experts” offering advice.The results of our experiment generate several interesting findings. The raw bid data suggest that subjects bid significantly more for data than they do for advice. Second, in the market for advice there appears to be no consensus as to who are the best advisors although on average economists demand the highest mean price and women suffer a discount. In addition, we find that whether a subject suffers from a representativeness bias in the way he or she processes data has an impact on how he or she bids for advice and on his or her willingness to follow it once offered. Finally, we find that on average people impute a low level of informativeness onto advice, consistent with their bidding behavior for data versus advice.This work was done under grant number SES-0425118 of the National Science Foundation. The authors would like to recognize the Center for Experimental Social Science at New York University for its additional support. We also acknowledge the help of Elizabeth Potamites for her research assistance.     

关于基尼系数若干问题的再研究--与部分学者商榷

基尼系数是测量收入不平等的一个重要指标，近年来有很多学者对此进行了深入研究，本文主要对有关学者的研究内容进行商榷与补充。首先，实际计算基尼系数应首选离散公式，并且根据具体的抽样方法选择无偏或有效的估计公式；其次，本文论证了对数正态分布下基尼系数G与标准差d的关系式：G=2Ф（σ/√2）-1；再次，针对基尼系数存在的不足，改进基尼系数成为一些学者的研究重点，本文发现一些改进并没有解决基尼系数与洛伦茨曲线的非一一对应问题，并且可操作性较差，通过介绍S基尼系数和E基尼系数，本文说明了基尼系数改进的总体思路；最后，针对学者提出的“部分分布决定性定理（PD定理）”，本文论证了其推理过程中存在的问题，说明该定理是错误的。     

More pessimism than greediness: a characterization of monotone risk aversion in the rank-dependent expected utility model

Summary. This paper studies monotone risk aversion, the aversion to monotone, mean-preserving increase in risk (Quiggin [21]), in the Rank Dependent Expected Utility (RDEU) model. This model replaces expected utility by another functional, characterized by two functions, a utility function u in conjunction with a probability-perception function f. Monotone mean-preserving increases in risk are closely related to the notion of comparative dispersion introduced by Bickel and Lehmann [3,4] in Non-parametric Statistics. We present a characterization of the pairs (u,f) of monotone risk averse decision makers, based on an index of greediness G _u of the utility function u and an index of pessimism P _f of the probability perception function f: the decision maker is monotone risk averse if and only if . The index of greediness (non-concavity) of u is the supremum of taken over . The index of pessimism of f is the infimum of taken over 0 < v < 1. Thus, , with G _u = 1 iff u is concave. If then , i.e., f is majorized by the identity function. Since P _f = 1 for Expected Utility maximizers, forces u to be concave in this case; thus, the characterization of risk aversion as is a direct generalization from EU to RDEU. A novel element is that concavity of u is not necessary. In fact, u must be concave only if P _f = 1.Received: 10 April 2001, Revised: 18 November 2003, JEL Classification Numbers: D81. Correspondence to: Michéle CohenAlain Chateauneuf, Michéle Cohen, Isaac Meilijson: We are most grateful to Mark Machina, Peter Wakker and two anonymous referees for very helpful suggestions and comments.     

Discrepancies between ex ante and ex post efficiency under identical subjective probabilities

Summary. Starr (1973) showed that, if people have different subjective probabilities, ex ante and ex post efficiency conflict. Conversely, under the simple preferences that he considered, the discrepancy between ex ante and ex post efficiency disappears when subjective probabilities are identical. Here I consider identical subjective probabilities, but more general preferences. First, risk attraction is admitted. Second, I dispense with the double requirement (dubbed IZU) of additive separability and state-independence of the utility of zero-date consumption, an unrealistic requirement when modeling the investment in durable goods. I find that, under IZU, and as long as ex post preferences satisfy the natural assumption of quasiconcavity (and satisfy some technical qualifications), an ex ante efficient allocation is indeed ex post efficient, but the converse is not necessarily true under risk attraction. If, on the other hand, IZU is violated, then one can have ex ante efficient allocations that are not ex post efficient, and vice-versa, even under risk aversion. Received: June 25, 1999; revised version: March 2001     

新疆城市居民收入不平等现状分析

本文采用基尼系数及其分解公式对新疆2003年城市居民收入调查的2828个样本数据进行分析，根据新疆的地理特征将基尼系数按南疆与北疆进行分解计算，并按收入来源对基尼系数进行集中度分解分析，结果表明新疆的收入不平等状况并不严重，南疆的收入差距大于北疆，工资收入和转移收入是收入差距增大的主要原因。     

中国的消费不振与收入分配:理论和数据

本文根据消费理论的最新发展对收入分配与总需求关系的认识 ,结合中国的具体国情 ,建立了一个用于解释中国消费不振的理论框架 ,并较好地说明了其它理论所不能解释的一些消费特征。最后提出政策建议。     

Forecasting UK house prices: A time varying coefficient approach

Previous studies of UK house prices, developed from the demand and supply ofhousing or from the asset market approach have been poor in terms of robustness and ex-post forecasting ability. The UK housing market has suffered a number of structural changes, particularly since the early 1980s with substantial house price increases, financial market deregulation and the removal of mortgage market constraints through competition. Consequently, models which assume that the underlying data-generating process is stable and apply constant parameter techniques tend to suffer in terms of parameter instability. This article uses the Time Varying Coefficient (TVC) methodology where the underlying data-generating process in the UK housing market is treated as unstable. The estimation results of the TVC regression of UK house prices is compared with those obtained from three alternative constant parameter regressions. Comparisons of forecasting performance suggest the TVC regression out-performs forecasts from an Error Correction Mechanism (ECM), Vector Autoregressive (VAR) and an Autoregressive Time Series regression.     

Cross-sectional earnings risk and occupational sorting: The role of risk attitudes

This paper investigates to what extent individuals' risk preferences are correlated with the cross-sectional earnings risk of their occupation. We exploit data from the German Socio-Economic Panel, which contains a direct survey question about willingness to take risks that has been shown to be a behaviorally valid measure of risk aversion. As a measure of earnings risk, we use the cross-sectional variation in earnings that is left unexplained by human capital variables in Mincerian wage regressions. Our evidence shows that individuals with low willingness to take risks are more likely to work in occupations with low earnings risk. This pattern is found regardless of the level of occupation categories, region, gender and labor market experience.     

论美国风险投资维护金融安全的经验及启示

风险投资对于维护金融安全而言有利也有弊,而美国风险投资却趋利避害,不仅促进了美国实体经济的发展,也为稳定美国金融安全作出了贡献。究其原因,美国风险投资有科学的组织模式、广泛的资金来源、谨慎的投资方式的选择、健全的服务与监管体系,而且还有美国政府的大力支持。本文以美国的成功经验为鉴提出了发展我国风险投资的一些看法。