首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Deterministic evolutionary dynamics: A unifying approach   总被引:1,自引:0,他引:1  
We tackle three components of evolutionary modelling: payoffs, dynamical systems and equilibrium concepts. Firstly, we merely require that fitness functions are continuous. Secondly, we examine very general classes of dynamics. Thirdly, we give useful parallels to the Nash equilibrium and the evolutionarily stable strategy. Under (weakly) sign-compatible dynamics the change in population share of every (at least one) subgroup present in the population corresponds in sign with its relative fitness. At a saturated equilibrium, each subgroup with positive population share has highest fitness. We examine two evolutionary stability concepts: the evolutionarily stable equilibrium and the generalized evolutionarily stable state.  相似文献   

2.
In general rational expectations equilibrium (REE), as introduced in Radner (Econometrica 47:655–678, 1978) in an Arrow–Debreu–McKenzie setting with uncertainty, does not exist. Moreover, it fails to be fully Pareto optimal and incentive compatible and is also not implementable as a perfect Bayesian equilibrium of an extensive form game (Glycopantis et al. in Econ Theory 26:765–791, 2005). The lack of all the above properties is mainly due to the fact that the agents are supposed to predict the equilibrium market clearing price (as agent’s expected maximized utility is conditioned on the information that equilibrium prices reveal), which leads inevitably to the presumption that agents know all the primitives in the economy, i.e., random initial endowments, random utility functions and private information sets. To get around this problematic equilibrium notion, we introduce a new concept called Bayesian–Walrasian equilibrium (BWE) which has Bayesian features. In particular, agents try to predict the market-clearing prices using Bayesian updating and evaluate their consumption in terms of Bayesian price estimates, which are different for each individual. In this framework agents maximize expected utility conditioned on their own private information about the state of nature, subject to a Bayesian estimated budget constraint. Market clearing is not an intrinsic part of the definition of BWE. However, both in the case of perfect foresight and in the case of symmetric information BWE leads to a statewise market clearing; it then becomes an ex post Walrasian equilibrium allocation. This new BWE exists under standard assumptions, in contrast to the REE. In particular, we show that our new BWE exists in the well-known example in Kreps (J Econ Theory 14:32–43, 1977), where REE fails to exist. This work was done in the Spring of 2005, when EJB was a visiting professor at the University of Illinois.  相似文献   

3.
The paper derives conditions for eductive stability of rational expectations equilibria in simple linear economic models with private information. Following Guesnerie (1992; 2002), the concept of eductive stability is used. It is shown that even in a private information setting, rational expectations equilibria might be justified as a result of mental process of reasoning of the agents. The paper considers an equilibrium concept, where the agents are unable to condition their forecasts on the actual market price. It is shown that eductive stability in this case requires that a condition is satisfied that is also relevant in the symmetric information case. This condition is compared to the respective stability condition that must hold if agents are able to use the current market price as an additional source of information. It turns out that the conditions for eductive stability that emerge under both equilibrium concepts differ.revised version received September 11, 2003  相似文献   

4.
中国棉花期货和现货市场的价格关系研究   总被引:10,自引:0,他引:10  
李慧茹 《经济经纬》2006,(5):149-151
期货市场和现货市场之间的价格发现功能一直是监管部门和投资者十分关心的问题。本文借助信息共享模型、脉冲响应函数和方差分解等方法,对中国棉花的期、现货市场间的价格关系进行实证研究,定量刻划了期、现货市场在价格发现中的作用。研究结果表明:棉花期、现货价格之间存在显著的双向引导关系;二者存在长期均衡关系;期、现货市场都扮演重要的价格发现角色,期货市场在价格发现中处于主导地位。  相似文献   

5.
This paper studies the effect of asymmetric information on the price formation process in a quote-driven market. One market-maker receives private information on the value of the quoted asset and repeatedly competes with market-makers who are uninformed. We show that despite the fact that the informed market-maker's quotes are public, the market is never strong-form efficient with certainty until the last stage. We characterize a reputational equilibrium in which the informed market-maker influences and possibly misleads the uninformed market-makers' beliefs. At this equilibrium, a price leadership effect arises, the informed market-maker's expected pay-off is positive and the rate of price discovery increases in the last stages of trade.  相似文献   

6.
This paper evaluates Schumpeter's grand vision as reflected in his Capitalism, Socialism and Democracy, and elaborates it in conjunction with the so-called “globalization” trends characteristic of the wake of the twenty-first century. In addition to the evolutionary nature of his methodology, the institutionalist dimension of Schumpeter's definitions are brought to light. A case is made for a fundamental process of “uncreative destruction” as far as the institutional setup of the economy is concerned. The contention of this paper is that there is ample support in Schumpeterian analysis for a counterpoint to the liberal thesis that envisages the worldwide spread of individualism, market economies, and democratic forms of government.  相似文献   

7.
This paper studies the equilibrium of an exchange economy with the same number of agents and commodities. It is shown that under rather mild conditions on demand the market have a price equilibrium—independently of the divisibility of the commodities. The result extends Gale’s equilibrium theorem for indivisible commodities to the case where some commodities are perfectly divisible. The proof is based on a topological lemma contained in previous paper of one of the authors.  相似文献   

8.
Localized knowledge percolation processes and information networks   总被引:2,自引:0,他引:2  
Summary The development of knowledge within industries is strongly influenced by the network structure of relations among firms. Firms relying on localized knowledge can implement their technological capability not only by means of research and development expenditures and internal learning but also through the systematic absorption of technological and scientific externalities available in their environment. Percolation processes have been studied in physics as the outcome of two classes of forces termed as connectivity and receptivity. The former measures the number of connections in place among the agents in the network and the latter the capability of each agent to absorb the informations received. This paper applies the methodology of percolation processes to operationalize the implications for both the economics of innovation and for technology policy of the structural characteristics of innovation networks as communication systems.  相似文献   

9.
This paper builds an observable delay game in endogenous timing to study the possible occurrence of trade wars in a vertical, bilateral trade model. It examines the effects of production cost differences and order of moves on optimal tariffs, market equilibria, dumping margin and social welfare in both fixed timing and endogenous timing games. In a fixed timing game, it shows that price dumping in the intermediate good market arises from differences in country-specific final good production costs. Different from Bernhofen (1995; Journal of International Economics), trade costs resulting from reciprocal tariffs in upstream markets can reverse the price dumping under certain conditions. In an endogenous timing game, this paper finds that the magnitude of cost differences significantly influences countries’ decisions on the order of moves in a strategic tariff-making game. Both countries want to be the first movers under a small cost difference and consequently reach a simultaneous equilibrium result. This demonstrates that the second-best equilibrium proceeds under certain conditions. Under a large cost difference, sequential policy-making is the subgame perfect Nash equilibrium. If the cost difference is sufficiently large, both countries have an incentive to launch a trade war as a multiple equilibrium game.  相似文献   

10.
Conventions,local interaction,and automata networks   总被引:1,自引:0,他引:1  
This paper deals with the evolution of conventions in a finite population of boundedly rational players. We apply methods from the theory of automata networks to analyze the effects of different interaction structures. It is shown that the size of the reference group for each player has an important impact on the evolutionary stability of a particular convention, and that the interaction structure crucially determines the distribution of conventions in the population.  相似文献   

11.
Firm survival in the German automobile industry   总被引:1,自引:0,他引:1  
In this paper, methods of duration analysis are applied to investigate determinants of firm survival in the German automobile industry during the period 1886–1939. A new comprehensive data set has been assembled in order to secure data comparable to that for the US automobile industry. Our results show that the forces shaping the survival pattern of firms over the life cycle are quite similar in both countries, i.e. early entry in the life cycle and prior experience are associated with a lower risk of exit. This finding holds equally when parametric, semiparametric and nonparametric methods are applied.We thank the participants of the 10th conference of the International Schumpeter Society in Milan, June 2004, and the 31st EARIE conference in Berlin, September 2004, for helpful discussion. We also thank two anonymous referees for their comments. All remaining errors are in our responsibility.  相似文献   

12.
农产品期货市场套利并不充分,交易者也不是完全理性的。本文假设农产品期货市场有限套利、交易者异质信念并遵循“经验法则”预期,构建了农产品期货投机均衡定价模型,并认为集中竞价规则下产生的农产品期货价格是由交易者的预期决定的;前期期货价格水平、现货价格和前期期货价格的变动趋势、不同类型交易者的比例结构及其预期模式共同影响农产品期货价格的形成与波动;基本分析法交易者占主导地位的农产品期货市场具有更高的套期保值与价格发现效率。针对中国七种主要农产品期货的实证结果显示,农产品期货投机均衡定价模型对解释中国农产品期货价格的形成与波动是有效的。这意味着在期货行情系统中实时披露现货价格信息,培育和引导交易者运用基本分析法预测期货价格走势,有助于提升农产品期货市场的效率。  相似文献   

13.
The slow and endogenous twist of economic macro-structure makes up an important evolutionary feature of capitalist economies, and may be at the root of structural crisis. In this line, a Goodwinian growth model with increasing returns and profit-sharing that tries to picture a simple scenario of the seventies crisis is considered. It is shown that the exhaustion of the Kaldor-Verdoorn “productivity law” can entail, in a nonlinear framework, a “catastrophic” bifurcation from a “high” to a “low” growth path. Slow/fast dynamical systems then allow one to formalize a multiple time-scales dynamics where the growth path is shaped by the structural framework in which it takes place, but has also a long -un feedback. Structural change and crisis appear as long term and endogenous outcomes.  相似文献   

14.
We analyse the effects of a recent financial reform (Shanghai-Hong Kong Stock Connect) that enables cross-market investment between Hong Kong and Shanghai stock exchanges. Using a VECM, we find that the reform announcement considerably narrows the equilibrium level of price disparity and strengthens the price comovement of shares that are cross-listed in both markets. The estimated equilibrium relationship is in support of the relative law of one price. We find that both markets adjust in response to a disequilibrium in price disparity, leading to a sizeable error correction activity. The Shanghai market contributes to approximately two-thirds of the price discovery process. Competition and informativeness of trading affect the relative role of price discovery in each market. Finally, the reform implementation reinforces the long-run cointegration relationship and strengthens the short-run price comovements of cross-listed stocks despite the widening price disparity during the period.  相似文献   

15.
We present a simple model of trading in a financial market where agents are asymmetrically informed and information is transmitted through the price system. We characterize the equilibrium for this economy and show that ‘rational mispricing’ of assets occurs if the price system fails to reveal the insider information accurately. It is argued that the communication of wrong information through equilibrium prices is compatible with full rationality on the part of the investors and may explain deviations from the efficient markets hypothesis.  相似文献   

16.
Consider a decentralized, dynamic market with an infinite horizon and incomplete information in which buyers and sellers' values for the traded good are private and independently drawn. Time is discrete, each period has length δ, and each unit of time a large number of new buyers and sellers enter the market. Within a period each buyer is matched with a seller and each seller is matched with zero, one, or more buyers. Every seller runs a first price auction with a reservation price and, if trade occurs, the seller and winning buyer exit with their realized utility. Traders who fail to trade either continue in the market to be rematched or exit at an exogenous rate. We show that in all steady state, perfect Bayesian equilibria, as δ approaches zero, equilibrium prices converge to the Walrasian price and realized allocations converge to the competitive allocation.  相似文献   

17.
The authors' aim was to analyze the influence of analysts' recommendations on the activity of informed and uninformed traders and whether such influence produces changes in the price discovery process. The analysis was carried out in the Spanish market, considered to be an ideal market given its characteristics. The authors' results indicate that although investors as a whole react to new information from analysts and their activity increases, this reaction is not independent of the type of stock. Informed traders do not increase their activity with small stocks to the same extent as uninformed investors do. Furthermore, the influence of these movements on price discovery is not significant. The results suggest that the interpretation role of analysts is more important for less accessible firms in terms of assessing their growth opportunities. This role may enhance the herding behavior of uninformed agents trading in those small titles for which they would otherwise need to invest extra time and extra money for taking profitable decisions.  相似文献   

18.
本文利用完全信息混合战略动态博弈方法对中国城镇住房市场销售者与购买者交易过程进行博弈分析。根据精炼纳什均衡解,在销售者预期市场条件不变的情况下,住房最优定价由销售者交易时间贴现因子决定,且与贴现因子呈反向变化关系;在预期市场条件变化情况下,最优定价由贴现因子与市场条件变动系数共同决定。  相似文献   

19.
企业并购交易决策博弈分析   总被引:4,自引:0,他引:4  
企业并购是并购交易双方在追求各自利益最大化的前提下所进行的博弈过程。由于企业并购交易市场的信息不对称性和不完美性,企业并购交易将会出现市场完全成功、部分成功、接近失败和完全失败四种不同性质和效率的市场均衡,其中只有市场完全成功是最理想和有效率的均衡。但在具体的企业并购交易中出现哪种均衡,主要取决于企业并购交易博弈模型中不同质量目标企业的价值、交易价格、风险成本和质量高、低比例之间的相互关系。减少出现上述三种低效率均衡机会的最有效方法是克服企业并购交易市场的信息不对称性问题,并提高并购企业的识别能力。  相似文献   

20.
Abstract. In this paper we look at unemployment as a phenomenon which reflects the co-ordination problems that characterize out-of-equilibrium processes of adjustment. The analysis carried out shifts the focus from structural factors to the economic process. It shows that unemployment cannot be satisfactorily explained – and policy interventions devised – by focusing only on specific characters of the technology or confining the analysis to structural factors concerning the labour market. The co-ordination mechanisms of adjustment processes rather than the fundamentals of the economy appear, in this light, as the main determinants of differences in unemployment trends in different economies; and monetary policy comes back to the center of the stage as an essential element of the working of these mechanisms. RID="*" ID="*" We thank anonymous referees for their very useful comments, and Elena Lega for the helpful support to the simulation analysis carried out. Correspondence to: J.-L. Gaffard  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号