A theorem on open coverings of a simplex and Scarf's core existence theorem through Brouwer's fixed point theorem

Summary This paper provides simple proofs of a theorem on open coverings of a simplex and Scarf's core existence theorem through Brouwer's fixed point theorem.I want to thank Daniel Abrams, Yakar Kannai, Herbert Scarf, Nicholas Yannelis, Jingang Zhao, and an anonymous referee for their helpful comments. I also gratefully acknowledge the financial support from the Alfred P. Sloan Foundation.     

All for one,one for all: Coopetition and virtual team performance

This study establishes a model based on coopetition theory to explain the formation of team performance in virtual teams. We tested the model in information technology (IT) organizations, and found applicability of coopetition in influencing team performance and knowledge sharing. Knowledge sharing is indirectly influenced by team politics and social capital (i.e., trust, social interaction and shared vision) via the mediation of cooperation and competition, while team performance is indirectly affected by team politics and social capital via the mediation of cooperation, team emotional intelligence and team competence.     

Does corporate governance play an important role in BHC performance? Evidence from the U.S.

This study explores the relationship between the operating performance and corporate governance of bank holding companies (BHCs) in the U.S. The modified data envelopment analysis (DEA) is utilized to integrate the five rating indicators of CAMEL (Capital Adequacy, Asset Quality, Management, Earnings, and Liquidity) so as to estimate the BHCs' performance. This study also employs the modified tiered DEA to categorize 68 BHCs into three Tiers. Additionally, the truncated-regression is employed to discuss whether or not the corporate governance would affect the performance of BHCs. The empirical results present the trade-off relationship with CAMEL indicators in the Tier1—Efficient BHCs. Moreover, it has been found that there are negative impacts on BHC's performance from board size, outside directors, the average age of directors and CEO/Chairman duality, while there are positive impacts from the number of committee and Big-4 auditors. The results further prove that corporate governance is important for the operating performance of BHCs.     

排放权交易运行机制下我国企业排放成本的优化战略管理研究——基于企业目标和社会环保目标的实现

排放权交易运行机制下我国企业排放成本的优化战略管理对于实现"股东财富最大化"的企业目标和"节能减排、发展低碳经济"的社会环保目标具有重要的意义。本文阐述了排放成本优化战略管理与双重目标实现之间的相互作用机理,构建了二者的作用路径图,并为企业目标和社会环保目标的实现提供了一定的理论依据和具体措施。本文的研究丰富了排放权交易运行机制下我国企业排放成本战略管理研究领域的研究成果,对于"加快我国转变经济发展方式、促进经济可持续发展、实施低碳经济"的"十二五"规划的社会环保目标的实现具有积极的借鉴意义。     

Non-parametric method for European option bounds

There is much research whose efforts have been devoted to discovering the distributional defects in the Black–Scholes model, which are known to cause severe biases. However, with a free specification for the distribution, one can only find upper and lower bounds for option prices. In this paper, we derive a new non-parametric lower bound and provide an alternative interpretation of Ritchken’s (J Finance 40:1219–1233, 1985) upper bound to the price of the European option. In a series of numerical examples, our new lower bound is substantially tighter than previous lower bounds. This is prevalent especially for out of the money options where the previous lower bounds perform badly. Moreover, we present how our bounds can be derived from histograms which are completely non-parametric in an empirical study. We discover violations in our lower bound and show that those violations present arbitrage profits. In particular, our empirical results show that out of the money calls are substantially overpriced (violate the lower bound).     

家族控制、金融发展与上市公司现金股利政策

本文以中国A股上市公司为样本,考察家族控制、金融发展对于上市公司现金股利政策的影响。实证发现,家族上市公司的派现意愿和派现水平显著低于非家族上市公司,一个重要原因在于家族上市公司面临着比非家族上市公司更高的融资约束。进一步地,在良好的外部金融环境中,上市公司的派现意愿和派现水平显著更高,而且金融发展有助于缓解家族上市公司的融资约束问题并推动其现金股利的发放。     

中小商业银行个人网上银行差异化战略分析

信息技术和网络技术的蓬勃发展给金融业带来了巨大的变革,网上银行是金融信息化高级阶段的产物,它已经成为世界各国银行业发展的必然选择。文章立足中小商业银行的角度,探讨其发展个人网上银行业务的战略意义、实施差异化战略的必然选择及差异化战略的具体实施策略,以期为中小商业银行发展个人网上银行业务提供理论参考。     

关联交易还是信息优势?——基于国内证券投资基金重仓股的分析

由于国内证券投资基金制度上的特殊性,与许多上市公司拥有同一大股东,这一"金字塔"结构造成证券基金可能同时存在利益输送式的关联性投资或信息优势导致的获利性投资。本文通过对2005年至2010年所有基金公司季度重仓股持股数据的研究发现基金公司对其重仓股的交易的确存在着关联交易或信息优势的可能性。基金公司倾向于超买非关联性股票,这些股票在下一季度的收益与超买行为显著正相关,这表明基金公司可能拥有信息优势。对于关联性股票,基金公司则倾向于超卖,但下季股票收益与超卖行为并不显著相关,这可能是关联交易与信息优势两种可能性共同作用的结果。总体上看,国内基金的投资行为更多地由于信息优势所致。     

生态文明背景下政府推动居民生态消费的对策思考

人类生态足迹已超过地球生态承载力的50％,亟须以生态消费模式取代传统的资源耗竭型消费模式.生态消费在我国的倡导和实现,单纯依靠居民自发自觉尚不现实,需要政府、媒体和非政府组织等外部力量的推动,而政府在这一过程中应发挥主导作用.政府可通过基于消费价值的生态沟通等软性手段推动生态消费行为,同时引导企业、非政府组织等主体共同促进生态消费模式的普及.