Farsighted network formation

This paper studies a model of dynamic network formation when individuals are farsighted: players evaluate the desirability of a “current” move in terms of its consequences on the entire discounted stream of payoffs. We define a concept of equilibrium which takes into account farsighted behavior of agents and allows for limited cooperation amongst agents. We show that an equilibrium process of network formation exists. We also show that there are valuation structures in which no equilibrium strategy profile can sustain efficient networks. We then provide sufficient conditions under which the equilibrium process will yield efficient outcomes.     

Networks and farsighted stability

We provide a new framework for the analysis of network formation and demonstrate the existence of farsightedly consistent directed networks. Our framework extends the standard notion of a network and also introduces the notion of a supernetwork. A supernetwork is made up of a collection of directed networks (the nodes) and represents (via the arcs connecting the nodes) preferences and rules governing network formation. By extending Chwe's 1994 result on the nonemptiness of farsightedly consistent sets, we show that for any supernetwork there exists a nonempty subset of farsightedly consistent directed networks.     

Optimal product strategies in the presence of network externalities

A network externality exists when a user’s benefit from a product increases with the number of other users in the same network. We examine the possibility that a software firm may exploit network externalities by introducing a limited feature version of its commercially available software into the market. The two versions need not be perfectly compatible and network externalities are allowed to decline as the difference between the versions increases. We obtain conditions under which introducing a limited feature version is optimal.     

A network experiment in continuous time: The influence of link costs

In recent work on non-cooperative network formation star-shaped networks play an important role. In a particular theoretical model of Bala and Goyal (2000) center-sponsored stars are the only strict Nash networks. In testing this theoretical model, Falk and Kosfeld (2003) do not find experimental evidence that players select the center-sponsored star. Based on a slight modification of Bala and Goyal’s model, we design a network formation experiment in which, depending on link costs, periphery-sponsored stars and the empty network are the only strict Nash networks. We observe that almost all groups not only reach a strict Nash network once but also switch the center player in periphery-sponsored stars several times. The main innovation in our experiment is to use a continuous time framework which we believe to be a more realistic setting to study behavior in network formation situations and which makes coordination on stars much easier than simultaneous strategy adaptation in discrete time. Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s10683-006-9125-1. JEL Classification C72 · C92 · D81     

Knowledge dynamics in a network industry

In this paper, we model the impact of networks on knowledge growth in an innovating industry. Specifically, we compare two mediums of knowledge exchange: random interaction, and the case in which interaction occurs on a fixed architecture. In a simulation study, we investigate how the medium of knowledge exchange contributes to knowledge growth under different scenarios related to the industry's innovative potential. We measure innovative potential by considering the extent to which knowledge can be codified, and the available technological opportunities. Our results tend to support the conjecture that spatial clustering generates higher long-run knowledge growth rates in industries characterized by highly tacit knowledge, while the opposite is true when the degree of codification is important.     

In search of stars: Network formation among heterogeneous agents

This paper reports results from a laboratory experiment on network formation among heterogeneous agents. The experimental design extends the Bala–Goyal [Bala, V., Goyal, S., 2000. A non-cooperative model of network formation, Econometrica 68, 1131–1230] model of network formation with decay and two-way flow of benefits by introducing agents with lower linking costs or higher benefits to others. Furthermore, agents' types may be common knowledge or private information. In all treatments, the (efficient) equilibrium network has a “star” structure. While equilibrium predictions fail completely with homogeneous agents, star networks frequently occur with heterogeneous agents. Stars are not born but rather develop: with a high-value agent, the network's centrality, stability, and efficiency all increase over time. A structural econometric model based on best response dynamics and other-regarding preferences is used to analyze individual linking behavior. Maximum-likelihood estimates of the underlying structural parameters, obtained by pooling data from several treatments, allow us to explain the main treatment effects.     

网络经济对中国企业的影响和发展策略研究

网络经济的出现是市场经济和网络的相互融合，它使信息替代资本成为在经济中的主导，由于互联网具有跨越地域和快速传播的特性，从而能够使产品的交易变得低成本和高效率，并通过这些对传统产业产生了多方面的深远影响。文章分析了网络经济对经济理论以及企业管理带来的挑战和影响，探讨如何结合网络经济的发展和我国企业的实际情况，找出我国企业适应网络经济发展的创新机制和发展策略。     

One-way flow networks: the role of heterogeneity

I study a one-way flow connections model in which players are heterogeneous with respect to values and the costs of establishing a link. I show that values and costs heterogeneity are equally important in determining the level of connectedness and the architecture of equilibrium networks. I also show that when asymmetries are independent of the potential partner there are distributions of costs and values for which centrality is a distincitive feature of equilibrium networks. This sharply contrasts with the homogeneous case.I thank an anonymous referee for useful comments. The paper has benefited from discussion with Gabriella Conti, Jose Luis Moraga-Gonzalez, Fernando Vega-Redondo and Sanjeev Goyal.     

Existence of Nash networks in one-way flow models

This paper addresses the existence of Nash equilibria in one-way flow models in a number of different settings. In these models players form costly links with other players and obtain resources from them through the directed path connecting them. We find that heterogeneity in the costs of establishing links plays a crucial role for the existence of Nash networks. The paper also provides conditions for the existence of Nash networks in models where costs and values of links are heterogeneous. We would like to thank an anonymous referee for useful suggestions. We would also like to thank Hans Haller and participants at the AEA Meetings 2007 for helpful comments. Sudipta Sarangi acknowledges the support of NSF grant HSD-0527315 and the hospitality of CREUSET, Jean Monnet University.     

Evolution of networks—an experimental analysis

It is the main aim of our paper to study network formation in experimental setups in discrete and continuous time. Our design is inspired by the theoretical model on network formation by Bala and Goyal (Econometrica, 68(5): 1181–1229, 2000) as well as the experiments by Callander and Plott (J. Public Econ., 89: 1469–1495, 2005) and Falk and Kosfeld (IEW Working Paper, University of Zürich, Zürich, Switzerland, No. 146, 2003). In particular, we analyze the role of star-shaped networks which are strict Nash-equilibria of the corresponding network formation game. Our experimental results show that strict Nash networks prove to be a good indicator for predicting network formation, particularly in continuous time. In explaining our results, it turns out that, among others, the complexity in coordinating on stars, the inequity aversion against unequal payoff distribution in the network, and the groups’ degrees of activity are the most important determinants for the formation of strict Nash networks.      

谈沈阳满族的形成

满族是沈阳诸多少数民族中人口最多的民族,他们为沈阳城的发展做出了巨大的贡献。因此,主要依据历史,对沈阳满族的形成做了较为详细的分析。     

The role of small bettors in price formation in betting exchanges

ABSTRACT

The presence of small bettors in betting exchanges generates mispricing, which can lead to exploitation by informed traders or result in permanent price deviations. This paper shows that mispricing from this source is also dependent upon variables of established relevance such as tournament round, the level of attention to the event, the volume of the betting, and bet type, further confirming these findings by means of cumulative accuracy profile (CAP) curves. It also offers evidence of the relevant role played by the type of device used to place the bet, whereby higher mispricing is observed in live bets placed via a mobile device, which appears to be associated with impulsive betting. This last finding could have practical implications for the regulation of the use of mobile devices to access gambling platforms.     

Platform strategies: how the position in the network drives success

Scholars have focused on platform strategies for a long time, moving from a product perspective to an industry-wide one. In particular, the decision to open the platform to external complementors has been studied through the perspective of platform leadership. The digital age is now moving from a closed approach versus an open approach. Is being a platform leader still imperative or is participating in a network of existing platforms still a suitable strategy as well? What kind of collaborations within an ecosystem leads to better performances? Leveraging social network analysis is performed within the network formed by mobile apps in the Health and Fitness category; this research shows how the decision of being (or not) a platform provider has an impact on the performances, but the position within the network mediates this impact. Based on the results obtained, research and managerial implications can be established.     

法律英语的模糊性与翻译教学策略

模糊现象客观存在于人类语言中,作为自然语言之一的法律语言,则必然具有模糊性。在阐述法律英语模糊性产生的原因及其具有的语用功能的基础上,探讨了法律翻译教学中应对模糊现象的翻译策略,提出为了达到目的语与原语表达的等值,教师应指导学生遵守＂模糊度对等＂原则,但由于法律翻译重在理解和表达正确,因此＂模糊度对等＂的策略也要和传统的翻译方法相结合。     

网络经济虚拟性的理论分析与实证检验

网络经济在四十年的发展过程中,其投入产出的关系呈现出完全不同的阶段性特征,对这一现象的解释一直是学术界争论的热点。目前,西方经济学对此的解释争议较大,且缺乏整体性;由于网络经济中新的生产方式对马克思经典的劳动价值论提出了挑战,马克思主义经济学也不能很好地解释上述问题。我们以马克思的劳动价值论为基础,结合网络经济虚拟性的根本特征,对网络经济发展过程中不同阶段表现出的特征给出一个政治经济学的解释。     

The welfare effect of quality degradation in the presence of network externalities

This paper examines how the presence of network externalities affects a monopolist's incentive for quality degradation and its welfare consequence. The software and Internet service industries provide our primary motivation. The network externality may lead to a Pareto-improving quality degradation that would not be realised in the absence of network externalities. However, it may also overturn a potentially Pareto-improving quality degradation to a welfare-reducing one, or result in the realisation of a welfare-reducing quality degradation that would be avoided without network externalities. We also endogenise the firm's forward and backward compatibility decisions between the original and degraded goods.     

Actions influenced by a social network

A simple framework is presented in which, each period, each of N individuals chooses among K alternatives. Individual actions are interrelated through a social network which arrays the strength of influence of each person on each other person. Emphasis is on the role of the network. The framework accommodates a variety of particular contexts, suggests theorems, and unifies a sizable part of the fragmented literature on network interaction.     

The network of the Iranian techno-economic system

This is a quantitative study of Iranian techno-economic system at the disaggregated industry level. We measure interindustry technology diffusion in the manufacturing sector of Iranian economy in the framework of the Iranian interindustry transaction table and R&D-embodied product flows among the industries. Moreover, we used network analysis to gain a better understanding of the technological network of the manufacturing sector of the economy.Based on several indices that describe the aggregate technological network, we classify Iranian manufacturing sector as a dispersed, hierarchic system.We identified Chemicals and Chemical Products and Rubber and Plastics as the sectors with most powerful contacts in the network, and hence with the highest capability to diffuse technology in the network.We discovered that a large number of sectors in the Iranian innovation network do not diffuse or receive innovation from the other sectors of the economy, and present potential opportunities for widespread diffusion of innovations.     

On the evaluation of power in parliaments and government formation

This paper is devoted to the study of power in Parliaments. We explain how the power of coalitions can be computed after elections. We add to the existing literature by using this analysis to predict what government may emerge from these elections.