Endogenous timing of moves in an asymmetric price-setting duopoly

This paper adds to the growing literature on endogenous timing of decisions in duopolies. We show for a price-setting duopoly game with sufficiently asymmetric and strictly convex cost functions that the less efficient firm moves first while the more efficient moves second with a higher price than the less efficient firm.Received: October 2002, Accepted: March 2003, JEL Classification: D43, L13AttilaTasnádi : attila.tasnadi@wiwi.uni-bonn.deCorrespondence to : Department of Economics, University of Bonn, Adenauerallee 24-42, 53113 Bonn, GermanyAttilaTasnádi : I am grateful to Dan Kovenock and the anonymous referees for many comments and suggestions on an earlier version of this paper. Parts of this research were done during the authors Bolyai János Research Fellowship provided by the Hungarian Academy of Sciences (MTA).     

Strongly stable networks

We analyze the formation of networks among individuals. In particular, we examine the existence of networks that are stable against changes in links by any coalition of individuals. We show that to investigate the existence of such strongly stable networks one can restrict focus on a component-wise egalitarian allocation of value. We show that when such strongly stable networks exist they coincide with the set of efficient networks (those maximizing the total productive value). We show that the existence of strongly stable networks is equivalent to core existence in a derived cooperative game and use that result to characterize the class of value functions for which there exist strongly stable networks via a “top convexity” condition on the value function on networks. We also consider a variation on strong stability where players can make side payments, and examine situations where value functions may be non-anonymous—depending on player labels.     

On the formation of interaction networks in social coordination games

There are many situations where two interacting individuals can benefit from coordinating their actions. We examine the endogenous choice of partners in such social coordination games and the implications for resulting play. We model the interaction pattern as a network where individuals periodically have the discretion to add or sever links to other players. With such endogenous interaction patterns we see multiple stochastically stable states of play, including some that involve play of equilibria in the coordination game that are neither efficient nor risk-dominant. Thus the endogenous network structure not only has implications for the interaction pattern that emerges, but it also has a significant impact on the play in the coordination game relative to what would arise if the same interaction network were exogenous.     

Voting in small networks with cross-pressure

We present a model of participation in elections in small networks, in which citizens suffer from cross-pressures if voting against the alternative preferred by some of their social contacts. We analyze how the existence of cross-pressures may shape voting decisions, and so, political outcomes; and how parties may exploit this effect to their interest. We characterize the strong perfect equilibria of the game and show that, in equilibrium, the social network determines which party wins the election. We also show that to dispose of the citizens better connected in the network with the other faction is not a guarantee to win the election.      

Fair allocation in networks with externalities

I prove existence and uniqueness of a component efficient and fair allocation rule when the value of the network is allowed to exhibit any type of externalities across its components. This is done by means of a new specification of the value function, generalizing partial results appearing in Myerson [Myerson, R.B., 1977a. Graphs and cooperation in games. Math. Operations Res. 2, 225–229], Feldman [Feldman, B.E., 1996. Bargaining, coalition formation and value. PhD dissertation. State University of New York at Stony Brook] and Jackson and Wolinsky [Jackson, M.O., Wolinsky, A., 1996. A strategic model of social and economic networks. J. Econ. Theory 71, 44–74]. This component efficient and fair allocation rule is found closely related to an extension of the Shapley value to TU-games in partition function form proposed by Myerson [Myerson, R.B., 1977b. Values of games in partition function form. Int. J. Game Theory 6 (1), 23–31].     

Competition in telecommunication networks with call externalities

This paper describes a model involving two interconnected networks offering different degrees of quality. In these networks, there are call externalities enabling consumers to assess the quality of the calls they send and receive. Networks compete in two-part tariffs. Our aim is to show that the “profit neutrality” result no longer applies due to network asymmetry and call externalities. In the case of non reciprocal access charges, call externalities generate private incentives enabling each competitor to charge low access prices. This reduces the risk of tacit collusion as competitors are free to negotiate their access charges.      

我国贸易条件异常波动的内外冲击因素

针对2007年第二季度至2012年期间我国价格贸易条件异常波动的现象,文章利用可变参数状态空间模型,比较分析了相关要素的影响方向和力度。结果表明:(1)国外产出缺口、国际大宗商品价格和人民币升值是影响我国价格贸易条件异常波动的主要原因;(2)比较收入贸易条件的影响因素,国外产出缺口始终处于正向影响,人民币升值具有较强的负向影响,国际大宗商品价格和国内通货膨胀的影响较中性。     

中国股市机构投资者多账户交易行为研究

多账户交易行为是中国机构投资者的典型特征,是中国股票市场的特有现象。限于交易数据的可获得性,相关研究较少。本文提出了一种从交易数据中将机构投资者的交易记录分离出来的方法。据此,本文分析了机构投资者证券账户与资金账户的对应关系,证实了多账户交易行为的存在,发现采用多账户交易的机构投资者具有集中投资、日内多次交易、利用不同证券账户进行建仓、对敲、拉升股价、出货等基本特征。根据实证研究的结果并结合实例,本文揭示了机构投资者多账户交易的动机是隐蔽交易、拉升股价和申购新股。     

How bad is forming your own opinion?

The question of how people form their opinion has fascinated economists and sociologists for long time. In many of the models, a group of people in a social network, each holding a numerical opinion, arrive at a shared opinion through repeated averaging with their neighbors in the network. Motivated by the observation that in reality consensus is rarely reached, we study a related sociological model in which individuals' intrinsic beliefs counterbalance the averaging process and yield a diversity of opinions.We interpret the repeated averaging process as best-response dynamics in an underlying game with natural payoffs and its limit as an equilibrium. This allows us to study the cost of disagreement by comparing between the cost at equilibrium and the social optimum. We also consider a natural network design problem in this setting: which links can we add to the underlying network to reduce the cost at equilibrium?     

Information-sharing in social networks

We present a new model for reasoning about the way information is shared among friends in a social network and the resulting ways in which the social network fragments. Our model formalizes the intuition that revealing personal information in social settings involves a trade-off between the benefits of sharing information with friends, and the risks that additional gossiping will propagate it to someone with whom one is not on friendly terms but who is within oneʼs community. We study the behavior of rational agents in such a situation, and we characterize the existence and computability of stable information-sharing configurations, in which agents do not have an incentive to change the set of partners with whom they share information. We analyze the implications of these stable configurations for social welfare and the resulting fragmentation of the social network.     

Farsightedly stable networks

A set of networks G is pairwise farsightedly stable (i) if all possible farsighted pairwise deviations from any network g G to a network outside G are deterred by the threat of ending worse off or equally well off, (ii) if there exists a farsighted improving path from any network outside the set leading to some network in the set, and (iii) if there is no proper subset of G satisfying conditions (i) and (ii). A non-empty pairwise farsightedly stable set always exists. We provide a full characterization of unique pairwise farsightedly stable sets of networks. Contrary to other pairwise concepts, pairwise farsighted stability yields a Pareto dominant network, if it exists, as the unique outcome. Finally, we study the relationship between pairwise farsighted stability and other concepts such as the largest pairwise consistent set and the von Neumann–Morgenstern pairwise farsightedly stable set.     

Principles for the design of management control systems in knowledge networks: Experiences involving the European technology networks

The aim of this paper is to analyse technology-knowledge networks, especially the aspects relating to management control. The management of technology knowledge in a network is characterised by a number of special features that are typical of this form of organization, on the basis of which, we point out the main obstacles and disadvantages that condition the achievement of efficiency of their management. We will analyse management in these networks in light of the experience of various European institutions that actively participate in networks for the development of technological projects. The principal mechanisms used for the control of management will be obtained from the empirical study. Finally, on the basis of the empirical verification, we will consider the development of certain general principles for control in order to achieve greater efficiency in the management of knowledge in these networks.     

证券交易机制影响股价吗?——对中国股票市场的再检验

本文在对分别按照开盘价和收盘价计算的两种收益率的比较中发现了极值聚集现象 ,文中将形成这一现象的原因归结于市场中涨跌幅限制的存在 ,并建立了一个简单模型对此进行了说明。其后 ,利用市场中不存在涨跌幅限制时期的数据对该模型进行了验证。在结论部分 ,本文分析了除交易机制外造成两种收益率差异的其他因素 ,并认为有关交易机制对股价行为影响的研究有待深入。     

Bayesian learning in social networks

We extend the standard model of social learning in two ways. First, we introduce a social network and assume that agents can only observe the actions of agents to whom they are connected by this network. Secondly, we allow agents to choose a different action at each date. If the network satisfies a connectedness assumption, the initial diversity resulting from diverse private information is eventually replaced by uniformity of actions, though not necessarily of beliefs, in finite time with probability one. We look at particular networks to illustrate the impact of network architecture on speed of convergence and the optimality of absorbing states. Convergence is remarkably rapid, so that asymptotic results are a good approximation even in the medium run.     

Resource price trends and development prospects

If natural resource prices follow exogenous paths, then future resource price changes must be reflected in current measures of resource depletion, as shown by Vincent et al. (1997). This result is extended to the measurement of income and saving in a small resource exporting economy. A precise formula for net (genuine) saving is derived when resource prices grow exogenously at the international interest rate. Empirical results are presented for over 100 countries and a dozen resource commodities, using historical real price trends to forecast future prices. Reductions in saving in excess of 1% of GNI are observed for over 20 countries.JEL Classification: F18, Q01, Q32, Q56 Correspondence to: Kirk HamiltonKatharine Bolt: The opinions expressed are those of the authors and not necessarily those of the World Bank. The financial support of the Swedish International Development Agency is gratefully acknowledged.     

Retailers as agents and the limits of parallel trade

The volume of retail-level parallel trade is surprisingly small despite persistent international price differences. We offer an agency-based explanation by considering competition between an original home manufacturer and a foreign retailer. The model endogenizes the role of the retailer as an agent with private information on the perceived quality of the good in its own market. The manufacturer cannot control the retailer once the latter has ordered its sales quantity but it can limit the initial offer. If parallel trade is permitted, this offer will fall if there is incomplete information, resulting in a small, or zero, volume of parallel trade. This outcome makes both the original producer and foreign consumers worse off, while offering little benefit to home consumers, compared to the case where such trade is banned.     

Returns from social capital in open source software networks

Open Source Software projects base their operation on a collaborative structure for knowledge exchange in the form of provision or reception of information, expertise and feedback on the creation of source code. Here, we address the direction of these knowledge flows among projects throughout social networks and their impact on project success. We identify the roles of membership or contribution that individuals play within projects. We found that connections through contributors who bring their knowledge to the project, improve project success, and that connection through members, who transfer their knowledge towards other projects, enhance project success. Finally, we found that ties through shared membership and contributions hamper project success. The analysis of knowledge flows and their impact on project success imply a translation of returns from investment in social capital, where investment takes the shape of knowledge flows and the returns mean the projects’ diffusion over the network.

Social capital, inclusive networks, and economic performance

Empirical studies show that the relationship between social capital and economic performance is ambiguous. The paper points to the potential trade-off between the sustainability of self-enforcement and the magnitude of gains from trade in social networks as an explanation. Based on an infinitely repeated multi-player prisoners’ dilemma it is shown how self-enforcement of cooperation within a network is influenced by its inclusiveness, its communication capacity, and the complexity of the exchange setting. The paper shows that inclusive social capital can combine both low enforcement costs and high gains from trade even in a complex exchange setting.     

俄罗斯金融市场套利交易的形成、影响及启示

20世纪90年代以来,俄罗斯在高度开放和自由的经济环境下,开展金融自由化改革,由此导致大量资本通过外债形式进入俄罗斯金融市场进行套利交易,套利资本推动俄罗斯经济、金融业的发展。而当套利资本迅速撤离俄罗斯市场时,俄罗斯金融市场就出现了银行业流动性吃紧、大规模抛售卢布现象,俄罗斯经济受到重创,最为典型的是1998年和2008年俄罗斯爆发的金融危机。文章试图通过研究俄罗斯的套利交易形成的影响因素,深刻理解俄罗斯金融危机。近年来,人民币不断升值,人民币跨境清算范围不断扩大,中国也面临着"热钱"监管压力,研究俄罗斯套利交易,对中国具有重要的借鉴意义。