中国股票市场市盈率的检验分析

市盈率高低是我国股市的关注焦点之一。本文在比较国外证券市场的市盈率之后认为我国的市盈率偏高。这种推测得到我们理论研究和模型结论的支持,我国股市市盈率由于系统风险的掩藏、股票初始发行价偏高和股市投机性等因素而呈现较高的倍数。从2004年我国股市市盈率开始下降,逐渐接近我们模型的估计值。此外,我们实证分析认为,市盈率的高低与GDP增长、股票收益波动和国有股比重等因素不存在严格的变动关系,市盈率呈现出一种随机游走的态势,市盈率不是稳定的区间值,而是一系列的动态的时间序列变量值。     

低保未就业人员求职意愿及影响因素研究

当前城市最低生活保障制度在运行过程中存在的一个突出问题,是低保对象中有劳动能力者的比重日益提高.运用北京市的调查数据,分析了若干经济、社会和心理(文化)因素对低保未就业者的求职意愿及行为的影响.研究发现:贫穷文化和社会资本对求职意愿、家庭规模对求职行为的影响作用具有统计显著性,工作与低保的比较效益以及就业援助则无显著影响.研究结果对进一步完善低保政策具有启发意义.     

外商直接投资行为分析及对策研究

中外学者的研究表明,外商直接投资对当地经济发展的促进作用是明显的,我国东部地区的经济发展就少不了外商直接投资的功劳。我国吸引外商直接投资已连续多年位居世界第二,而东部地区又是我国吸引外商直接投资最多的地区,占到了外商直接投资的85％以上。这表明外商在我国东、中、西部地区的直接投资很不平衡,外商直接投资的行为有着明显的特征。而且研究表明,他们的这些行为受到了诸如投资环境、地理位置、人力资源、经济外向度、聚集效应等因素的影响。因此各地特别是中西部地区,需要制定对策以提高外商在当地的直接投资。其中基本的对策是改善投资环境,丰富人力资源,产生聚集效应。     

我国证券市场风险收益特征的行为基础

我国证券市场的风险收益具有以下特征:(1)资本资产定价模型所揭示的风险收益关系在我国股市并不显著。(2)我国证券市场系统性风险占整体风险的比例较高。(3)从趋势上看,无论个股还是行业系统性风险占整体风险的指标没有明显的下降趋势。这些特征根源于我国特定的投资者结构以及不同投资者的风险厌恶特性和对私人信息的偏好特性。因此,投资者应针对上述特征,在集中投资、反向交易和降低交易频率等方面调整交易策略,提高投资收益率。     

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.     

论企业的双重属性

本文从企业人、资产、产品、价值、环境等与企业行为相关的五方面较为全面地分析了企业双重属性的内涵,指出企业必须认识到自己所天然具有的社会及经济属性,并以此作为指导企业发展设计和规范企业行为的意识准备。     

Money, Sex and Happiness: An Empirical Study

The links between income, sexual behavior and reported happiness are studied using recent data on a sample of 16,000 adult Americans. The paper finds that sexual activity enters strongly positively in happiness equations. Higher income does not buy more sex or more sexual partners. Married people have more sex than those who are single, divorced, widowed or separated. The happiness‐maximizing number of sexual partners in the previous year is calculated to be 1. Highly educated females tend to have fewer sexual partners. Homosexuality has no statistically significant effect on happiness.     

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     

Does seeing more deeply into a game increase one’s chances of winning?

The substantively rational value of the games studied in this paper does not help predict subject performance in the experiment at all. An accurate model must account for the cognitive ability of the people playing the game. This paper investigates whether the variation in measured rationality bounds is correlated with the probability of winning when playing against another person in games that exceed both players’ estimated rationality bound. Does seeing deeper into a game matter when neither player can see to the end of the game? Subjects with higher measured bounds win 63 percent of the time and the larger the difference the more frequently they win.