Researching with whom? Stability and manipulation

This paper explores the existence of stable research teams, when the preferences of each agent depend on the set of researchers who are collaborating. We introduce a property over researchers’ preferences, called top responsiveness, guaranteeing the existence of stable research teams configurations. We also provide a stable mechanism, induced by the so-called top covering algorithm, which is strategy-proof when researchers preferences satisfy top responsiveness. Furthermore, we find that, in this framework, the top covering mechanism is the only strategy-proof mechanism that always selects stable allocations.     

Stability and Segregation in Group Formation

This paper presents a model of group formation based on the assumption that individuals prefer to associate with people similar to them. It is shown that, in general, if the number of groups that can be formed is bounded, then a stable partition of the society into groups may not exist. (A partition is defined as stable if none of the individuals would prefer be in a different group than the one he is in.) However, if individuals' characteristics are one-dimensional, then a stable partition always exists. We give sufficient conditions for stable partitions to be segregating (in the sense that, for example, low-characteristic individuals are in one group and high-characteristic ones are in another) and Pareto efficient. In addition, we propose a dynamic model of individual myopic behavior describing the evolution of group formation to an eventual stable, segregating, and Pareto efficient partition. Journal of Economic Literature Classification Numbers: C72, H41.     

What do interest rates reveal about the functioning of real business cycle models?

This paper begins by documenting the extent to which the predictions of standard Real Business Cycle (RBC) models are incompatible with observed movements in real interest rates. The main finding of the paper is that extending the baseline model to include habit persistence in consumption and adjustment costs to capital significantly improves the model's empirical performance. In our evaluation of the model's performance, we take special care of estimating and testing predictions of the model using both moments drawn directly from the data and moments calculated after identifying shocks to the stochastic trend.     

业主公约法律问题简论——一个比较法的观察

住宅小区内不同主体的权利之争对物权法提出了实务上和学理上的双重挑战。作为建筑物区分所有权人的自治规范,业主公约已经成为平衡诸主体权利的“宪法性”文件,从比较法的角度对其相关法律问题进行逐一梳理,将为更深入和更细致的研究提供一个稳固的基础。     

Equilibrium binding agreements under diverse behavioral assumptions

Summary. This paper extends the work of Ray and Vohra [3]. It ascertains which partitions of players will emerge and what actions will these players choose under each partition, when they can sign binding agreements and their actions have externalities. The emphasis, however, is placed on situations with multiple outcomes and how agents behave in the presence of such multiplicity. In particular, a deviating coalition considers all the likely outcomes that may prevail upon its deviation, and selects (if possible) a subset of them. Three augmentations of Ray and Vohra's [3] solution concept are defined, capturing three distinct behavioral assumptions. Efficiency of and the relation between the three notions are discussed. Received: October 9, 2001; revised version: April 22, 2002 RID="*" ID="*" I wish to thank Licun Xue, Joseph Greenberg and the participants of PET 2000 for very helpful suggestions. I am indebted to an anonymous referee for his/her valuable comments. The paper has been previously circulated under the title Binding Agreements.     

经济增长、结构调整的累积效应与资本形成——当前经济增长态势分析

1990年以来 ,特别是 2 0世纪 90年代中后期 ,中国的经济结构发生了重大调整 :基础设施的投入奠定了城市化的基础 ,工业化在消费和出口的拉动下逐步升级。中国经济增长开始由工业化单引擎发展到工业化与城市化的双引擎。由低价工业化到高价城市化的转化以及与之相应的资金流程与资本形成方式的变化 ,一方面引起近年来中国经济的快速发展 ,另一方面也对未来中国经济的持续增长形成挑战。通过政府体制、金融体系和财税体制的进一步改革 ,完善资源配置方式 ,将是应对挑战、保持中国经济持续增长的保证。     

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     

Farsighted strategies in the formation of a communication network

I examine the formation of a specific communication network, a variant of the two-way flow model, in which agents have farsighted strategies. I show that the likelihood to form efficient networks tends to zero for sufficiently large network sizes.     

网络组织及其惯例的形成--基于演化论的视角

本文基于演化理论，构建了一个关于网络组织形成的动态模型。利用演化博弈论研究了网络组织内成员间关系和作用机制的形成过程。认为网络组织的形成是搜寻正收益的理性个体进行自发博弈的结果．基于网络组织成员之间反复行为的历史信息的反馈，形成了网络组织层面上的惯例机制，该惯例机制表现为一种运作机制和惯性作用，维持网络组织处于某一状态。     

一种新的机器人自组网群组运动控制模型

针对现有机器人自组网运动控制模型无法真实反映机器人运动规律的问题,提出一种新的群组运动控制模型(group movement control model,GMCM)。该模型基于机器人通用运动学模型,采用群组控制算法,对传统群组随机运动模型——参考点群组运动模型(reference point groupmobility,RPGM)进行修改,可描述机器人编队解散和集合的运动状态,满足群组分割与合并的需求。进一步实现GMCM模型,并基于GMCM,RPGM,DRGM模型对机器人自组网路由协议进行模拟仿真。结果表明,基于GMCM模型仿真时协议性能有所降低,较为真实地模拟了机器人编队运动,对机器人自组网的研究具有一定的参考价值。