Evolutionary stability and lexicographic preferences

We explore the interaction between evolutionary stability and lexicographic preferences. To do so, we define a limit Nash equilibrium for a lexicographic game as the limit of Nash equilibria of nearby games with continuous preferences. Nash equilibria of lexicographic games are limit Nash equilibria, but not conversely. Modified evolutionarily stable strategies (Binmore and Samuelson, 1992. J. Econ. Theory 57, 278–305) are limit Nash equilibria. Modified evolutionary stability differs from “lexicographic evolutionarily stability” (defined by extending the common characterization of evolutionary stability to lexicographic preferences) in the order in which limits in the payoff space and the space of invasion barriers are taken.     

Have Employment Relationships in the United States Become Less Stable?

There has been considerable debate as to whether job stability has declined in the United States. This paper uses data from the Survey of Income and Program Participation (SIPP) to examine the incidence of labor market turnover between 1986 and 1993. Specifically, we calculate one- and two-year separation rates and then analyze turnover by the source of separation. We find that the incidence of job separations did not increase over the period under investigation, but appears to have declined somewhat. When analyzing separations by reason, conditional on separating from an employer, we find little evidence of temporal changes in the composition of turnover that would indicate greater employment instability. Therefore, we do not find conclusive evidence that employment relationships have become more unstable in the recent past.      

Candidate stability and nonbinary social choice

Summary. The requirement that a voting procedure be immune to the strategic withdrawal of a candidate for election can be formalized in different ways. Dutta, Jackson, and Le Breton (Econometrica, 2001) have recently shown that two formalizations of this candidate stability property are incompatible with some other desirable properties of voting procedures. This article shows that Grether and Plott's nonbinary generalization of Arrow's Theorem can be used to provide simple proofs of two of their impossibility theorems. Received: August 15, 2001; revised version: March 11, 2002 RID="*" ID="*" Parts of this article were previously circulated in somewhat different form in a working paper with the same title by the second author. We are grateful to Michel Le Breton and an anonymous referee for their comments. Correspondence to:J.A. Weymark     

无界时滞中立型系统(非Razumikhin型)的稳定性

本文利用 Liapunov 函数法,建立无界时滞线性和非线性中立型系统(非 Razumikhin 型)稳定性的简单判据。     

The tortoise and the hare: the impact of employment instability on firm performance

The main objective of this study is to assess the influence of employment instability on firm performance in a sample of publicly traded firms. Competing theoretical arguments are considered with regard to likely outcomes associated with employment instability. A large sample of cross‐sectional time‐series data is then analysed using generalised estimating equations (GEE) regression techniques. Results indicate that employment instability is negatively associated with firm performance, although the relationship is also demonstrated to be quadratic (an inverse U‐shaped relationship). This suggests that the main relationship varies depending upon the level of employment instability. Industry characteristics are also examined as moderators of this main effect. The results suggest a disordinal interaction effect for industry differentiation, where employment instability is negatively associated with firm performance for firms in highly differentiated industries and positively associated in less differentiated industries.     

多级斜坡路基软弱地基变形机理和稳定性数值分析

山区公路路基往往是在斜坡上填筑的,这种填筑形式更易于发生变形破坏,故本文以某斜坡路基为研究对象,研究斜坡路基地基变形机理,并用强度折减法分析该斜坡路基的稳定性。结果表明:①地基形变的总体趋势以沉降变形为主,随填筑高度的增加,水平位移逐渐趋于均匀,并表现为侧向外鼓,沉降最大值集中在与填筑体中心相交的区域。②路基中心的最终沉降位移相较于坡脚的2倍;路基整体有向斜坡下滑移的趋势;短坡脚的水平位移发展最快。③斜坡路基随填筑高度的增加,从深层滑动发展为浅层滑动,滑体集中于长坡脚。④随填筑高度的增加,安全系数逐渐降低。     

机床再制造业交易稳定性差的影响因素实证研究

提出了导致机床再制造业交易稳定性差的影响因素：支持影响交易、售后影响交易、特性及认可度影响交易、需求影响交易，探讨了四因素与机床再制造产业交易稳定性差的关系，以227个企业为调查对象，对收集的数据进行分析。研究结果表明：各假设因素得分从高到低依次是特性及认可度因素、需求因素、支持因素和售后因素。不同性质的企业在再制造机床交易稳定性影响因素的支持、售后、需求以及总问卷上都存在显著差异。     

Impact of short selling activity on market dynamics: Evidence from an emerging market

With unique daily short sale data of Borsa Istanbul (stock exchange of Turkey), we investigate the dynamic relationship between short selling activity and volatility, liquidity and market return from January 2005 to December 2012 using a VAR(p)-cDCC-FIEGARCH(1,d,1) approach. Our findings suggest that short sellers are contrarian traders and contribute to efficient stock market in Turkey. We also show that increased short selling activity is associated with higher liquidity and decreased volatility. However this relation weakens during the financial turmoil of 2008. Our results indicate that any ban on short sales may be detrimental for financial stability and market quality in Turkey.     

重大水利工程项目决策社会稳定风险评估中的公众参与博弈

为改善重大水利工程项目决策社会稳定风险评估中公众参与现状,从社会稳定风险评估3个主要利益主体——中央政府、地方政府与公众不同的利益诉求出发,运用演化博弈模型,探讨在不同利益诉求的相互作用下影响地方政府与公众在社会稳定风险评估中策略选择的因素。研究发现,当公众受到的损失大于参与付出的成本时,双方稳定均衡状态均表现积极,反之,双方可能均表现为消极或积极这两种截然不同的状态。基于此,分析了中央政府对地方政府和公众在社会稳定风险评估博弈中策略选择的影响。最后,提出应加大对地方政府的支持、规范公众参与相关制度、加大教育培训及宣传力度、创新公众参与方式几项政策建议。     

Coalition formation in general apex games under monotonic power indices

An apex game consists of one apex player and a set of minor players. We identify two key properties of apex games and use them to introduce the class of general apex games. We derive players' preferences over winning coalitions by applying strongly monotonic power indices on such a game and all its subgames and investigate whether there are core stable coalitions in the induced hedonic coalition formation game. Besides several general results, in particular, we develop conditions on the game for the Shapley–Shubik index, the Banzhaf index, and the normalized Banzhaf index.