信息不对称、逆向选择和市场均衡

几乎所有研究信息不对称与逆向选择问题的文献都隐含着一家厂商在同一时刻只能提供单一质量水平产品的假设。本文在厂商可以同时提供高质量产品和低质量产品的假设基础上，通过建立模型来探讨信息不对称与逆向选择的关系。研究结论表明。当考虑到这一前提条件时，信息不对称所导致的逆向选择程度可能并不像先前的研究者所认为的那么严重，甚至可能不存在。此外，模型也指出，消费者所拥有的财富数量将严重地影响到逆向选择的程度，财富数量与逆向选择的严重程度存在着负相关关系。这个结论可以很好地解释在发展中国家假冒伪劣现象十分普遍的原因。最后，拟以浙江省龙井茶市场为例来验证本文所发展的理论。     

信息不对称、逆向选择与环保产业发展

文章构建了一个利润函数模型来分析信息不对称对环保产业发展的影响,得出:质量信息的不对称不但会导致环保产品市场的萎缩,社会福利得以损失,而且会影响环保产业的R&D投入水平,从而阻碍环保产业的健康持续发展。因此,有效地解决环保市场上的信息不对称问题,成为环保产业发展的关键。基于此,文章提出了四种途径:政府制定和实施相应的制度;企业发送信号;政府制定和实施相应制度与企业发送信号相结合;提高消费者的选购水平等。这可以为解决信息不对称提供新的思路,从而推动环保产业的发展。     

论区域旅游开发中信息不对称引致的逆向选择问题

文章基于对信息经济学理论相关观点的阐释,以上海市临港新城为例,提出了在区域旅游开发中信息不对称现象的产生及其原因,且对所引致的逆向选择问题作了分析,并探讨了相应对策,得出具有一定参考价值的结论。     

信息不对称与市场规制

本文通过对三位2001年度诺贝尔奖经济学家基本思想的分析。揭示了信息经济学的核心思想-逆向选择，信号传递，分离均衡之间的内在联系，并对如何进行市场规制克服信息不对称带来的市场失灵进行了理论探讨。     

信贷市场上投资项目的正逆向选择--不确定和不对称信息条件下投资项目正向和逆向选择的一般条件及转换

文章研究在不确定且信息非对称情况下,信贷市场上投资项目逆向和正向选择的一般条件.这里假设投资项目的结果只有两种,即要么成功,要么失败.我们定义并证明在一组仅具有两种结果的项目中,在成功概率-回报空间上存在一个逆向选择"区域"和一个正向选择"区域".Stiglitz和Weiss(1981)以及De Meza和Webb(1987)早先关于逆向选择和正向选择的案例实际上是一种特例,因为取决于所考察的项目情况,可以有无数个逆向和正向选择的情况.文章也考察了参数变化对企业家选择投资项目的比较静态影响,以及通过银行的某种决策组合把逆向选择转化为正向选择的可能性.     

信息不对称与非逆向选择

信息不对称引致逆向选择是信息经济学的重要观点。然而,实证研究对此提出挑战,学者们仅在部分保险市场发现逆向选择,还有大量市场出现正向选择或不相关选择。非逆向选择现象引起学界对传统信息不对称理论的反思,通过修正理论假设重新审视保险市场运行。学界研究表明,在双向信息优势、多维异质性和不完全风险分类假设下,保险市场可能出现逆向选择、正向选择或不相关选择。非逆向选择问题研究形成对传统信息不对称理论的拓展与完善,同时得到大量实证研究支持。     

保险市场信息不对称问题探讨

由于保险市场信息不对称,投保人无法了解保险产品质量,保险人对保险标的或被保险人的实际情况又不如投保人了解透彻,导致保险市场资源配置无效率,高质量保险无人买,而投保人的需求得不到满足,同时存在"逆向选择"和"道德风险"问题。本文通过分析保险市场信息不对称的表现形式及其原因,提出几点对策。     

逆向选择与资源配置效应

古典经济学中,往往假设市场中的所有参与者对有关交易的对象都具备完全、充分的信息,并因此通过市场这只“看不见的手”,使资源达到最优。实际上,现实世界是纷繁复杂的,在市场上往往有一些信息某些参与者拥有,而另一些参与者不拥有,这就是所谓的非对称信息。一旦这种情况出现,市场的运行将会出现新的特点,本文拟就非对称信息所引起的逆向选择问题做一粗浅的探讨。 　　一、何谓逆向选择 　　逆向选择是指在买卖双方信息非对称的情况下,差的商品总是将好的商品驱逐出市场。逆向选择的典型例子是在保险市场。例如你要投健康保险,你…     

我国农村信贷市场信息不对称问题及对策研究

在我国农村信贷市场上，信息不对称现象广泛存在，而信息不对称造成的逆向选择和道德风险则是不良贷款发生、农村金融抑制的重要原因。本文主要分析逆向选择和道德风险产生的原因，并提出了相关的对策，力求解决农村信贷市场上的信息不对称问题。     

论信息不对称条件下的消费信贷市场

消费信贷是银行为使消费者个人购买商品和劳务而向其提供的贷款 ,实为消费者用自己明天才能挣到手的钱来享受今天的生活。由于受信息不对称或不完全性的影响 ,经常会导致消费信贷市场供求的失衡。本文通过建立消费信贷市场均衡模型进行分析 ,阐述了由于信息不对称或不完全条件下其失衡的根源 :既有消费者方面的原因 ,又有银行方面的原因 ,更有二者共同缺乏消费信贷的积极性 ,由此提出了达到均衡的政策措施选择     

SEARCH,ADVERSE SELECTION,AND MARKET CLEARING

We examine a dynamic decentralized trading model with infinitesimal sellers and buyers to investigate whether or not the market fails to clear in the limit of search friction vanishing. A seller, who has private information about product quality, and a buyer are matched to bargain over price. They form a long‐term relationship if they reach agreement. They return to the matching pool if they fail to agree or the existing relationship is dissolved. The market fails to clear if and only if the ratio of agents' patience over the dissolution rate exceeds a threshold.     

ADVERSE SELECTION,LEARNING, AND COMPETITIVE SEARCH

I develop a model that allows for an analysis of the effects of time on adverse selection in the presence of search frictions. I find that, as a firm takes longer to adjust a worker's contract in response to learning about his type, inefficient overwork during the time before wage adjustment (probation) decreases. This provides a rationale for an optimal (minimum) probation period of about one month in the baseline scenario. Optimal probation duration varies with the degree of search frictions, the cost of effort, the relative productivity of different types of workers, and minimum wage regulations.     

DOUBLE‐SIDED ADVERSE SELECTION IN THE PRODUCT MARKET AND THE ROLE OF THE INSURANCE MARKET*

I investigate the interrelation between a product market and an insurance market when adverse‐selection problems exist both in consumers and in firms. Firms offer warranties for product failures. Consumers may further purchase first‐party insurance for the residual risks of product failures. Given that the insurance market exists, two types of equilibria are possible: (a) Different firm types offer different pooling warranties attracting both good and bad consumer types or (b) good firms attract only bad consumers and bad firms attract both types of consumers. I discuss the existence and the efficiency implication of the insurance market.     

MIDDLEMEN AND THE ADVERSE SELECTION PROBLEM

We demonstrate that the coexistence of an uncoordinated search market and a middleman market may alleviate adverse selection in the trade of goods of different quality. Inability to conduct trade penalizes sellers of low‐quality goods disproportionately, encouraging them to trade via middlemen. A semi‐separating equilibrium exists when a sufficient number of sellers of low‐quality goods choose the middleman market to allow high‐quality goods to be successfully traded in the search market. The result may explain why a search market can survive alongside a coordinated market, a phenomenon characteristic, for example, of markets for used cars, housing and labour.     

A NOTE ON ADVERSE SELECTION

A model of a labour market in which workers cannot signal their productivity is set up. The nature of adverse selection (too few good trades, too many bad trades, neither or both) is found to depend on the pattern of reservation wages.     

EVOLUTIONARY DRIFT IN PREFERENCE AND EQUILIBRIUM SELECTION*

This paper studies the situation where myopic players repeatedly face a society with two actions where their common fitness exhibits economies of scale. Both states in which all players choose the same actions are equilibria. In each period, players adjust their actions based on their preferences, which are in turn shaped by natural selection. The preferences of the players need not match the underlying fitness. When rare mutations are introduced into the evolutionary process, their preferences may drift without affecting equilibrium behaviour. This paper shows that these drifts influence the results of equilibrium selection.     

HUMAN CAPITAL ACCUMULATION AND LABOR MARKET EQUILIBRIUM*

We analyze an equilibrium labor market with on‐the‐job search and experience effects (as workers learn by doing). The analysis yields a Mincer wage equation with worker fixed effects and endogenously determined firm fixed effects. Equilibrium sorting—where over time more experienced workers also tend to move to better paid employment—has a significant impact on wage inequality.     

INFORMATION FRICTIONS AND HOUSING MARKET DYNAMICS

I examine the effects of seller uncertainty over their home value on the housing market. Using evidence from home listings and transactions data, I first show that sellers do not have full information about current period demand conditions for their homes. I incorporate this type of uncertainty into a dynamic microsearch model of the home selling problem with Bayesian learning. The estimated model highlights how information frictions help to explain the microdecisions of sellers and how these microdecisions affect aggregate market dynamics. The model generates a significant microfounded momentum effect in short‐run aggregate price appreciation rates.