ROBUST UTILITY MAXIMIZATION IN NONDOMINATED MODELS WITH 2BSDE: THE UNCERTAIN VOLATILITY MODEL

The problem of robust utility maximization in an incomplete market with volatility uncertainty is considered, in the sense that the volatility of the market is only assumed to lie between two given bounds. The set of all possible models (probability measures) considered here is nondominated. We propose studying this problem in the framework of second‐order backward stochastic differential equations (2BSDEs for short) with quadratic growth generators. We show for exponential, power, and logarithmic utilities that the value function of the problem can be written as the initial value of a particular 2BSDE and prove existence of an optimal strategy. Finally, several examples which shed more light on the problem and its links with the classical utility maximization one are provided. In particular, we show that in some cases, the upper bound of the volatility interval plays a central role, exactly as in the option pricing problem with uncertain volatility models.     

基于SVPWM的异步电机直接转矩控制系统研究

介绍了一种以TMS320LF2407A为核心的异步电机直接转矩控制系统.系统采用空间电压矢量脉宽调制技术得到逆变器的开关控制信号.实验结果表明,采用SVPWM 技术的异步电机直接转矩控制系统实现简单、性能优良,大大改善了电机的运行品质,提高了电压利用率.     

产业关联效应系数的经济含义及其定量分析——基于河北省主导产业选择的背景

统计分析及相关数据表明,在河北省,金属冶炼及压延加工业、机械工业、石油加工及炼焦业、化学工业以及电子通信设备制造业属于前向与后向关联度均大于平均值的行业,因而其在现实中也就应作为主导产业来加以扶持;此外,尽管仪器仪表及文化办公用机械制造业、商业、旅游业、金融保险业以及房地产业等产业的关联度没有上述金属冶炼及压延加工业等行业的关联度大,然而从发展前景上看,其也应成为全省经济发展的增长点。当然,实践中依据产业间产出的关联效应来选择主导产业,也应高度重视产业关联效应系数相对较低的农业等产业部门的发展。     

经济学方法论的逻辑要义

逻辑方法是科学研究的工具,这种工具作用在经济学研究中发挥到极致,以致经济学方法与逻辑方法密切程度有时难解难分,甚至是合二为一的。在经济学方法论史上,大多数的争论都集中在演绎方法和归纳方法孰优孰劣的问题上。随着科学哲学和现代逻辑的发展,经济学方法论中发生的证实与证伪、形式化与非形式化等争论,都源自于演绎方法与非演绎方法各自的作用及二者的关系这一根本问题。     

Order of Play, Forward Induction, and Presentation Effects in Two-Person Games

We investigate the effects of order-of-play (simultaneous, unobserved sequential and fully observed sequential play) and form of presentation (extensive vs. normal) in three simple two person games: battle-of-the-sexes with and without outside option and a three strategy game which differentiates between virtual observability (VO) and iterated elimination of dominated strategies as principles of equilibrium selection. VO predicts that knowledge of the order of play alone will affect the distribution of strategies chosen. We contrast this with the predictions of iterated elimination of dominated strategies. We report results from 1800 one-shot games conducted in 6 sessions with 120 subjects and analysed as panel data. The form of presentation strongly affects the distribution of outcomes and strategies. Information about order of play shifts the distribution of strategies away from the distribution in simultaneous play and towards the distribution in fully observed play, especially in the less complicated games presented in normal order. Order-of-play effects are less evident as complexity of the game increases. Extensive form presentation appears to induce sequential thinking even in simultaneously played games.     

Solomon's Dilemma: An experimental study on dynamic implementation

This paper reports an experimental investigation on two mechanisms for the so-called King Solomon Dilemma, where one of them fails to implement the social choice rule dynamically. We compare the two mechanisms in terms of their welfare, incentive and learning properties.Received: 9 October 2000, Accepted: 13 February 2003, JEL Classification: C70, C78The authors are grateful to José Agulló, Paolo Battigalli, Ted Bergstrom, Ken Binmore, Sandro Brusco, Antonio Cabrales, Francesco Feri, Leo Hurwicz, Raffaele Miniaci, Miguel Angel Meléndez, Juan Mora, Juan D. Moreno-Ternero and seminar participants at the universities of Alicante and Trento for stimulating comments. We also thank an anonymous referee for thoughtful comments and, in particular, for raising questions that led to run additional sessions that significantly improved Sect. 4.4. Usual disclaimers apply. The first version of this paper was written while Giovanni Ponti was visiting the Department of Economics at UCSB. He thanks the Department for providing hospitality, encouragement and funding to run some experimental sessions. Financial support was also provided by CICYT (BEC2001-0980) and by the Instituto Valenciano de Investigaciones Económicas (IVIE).     

简论科学史的方法论问题

本文从归纳和演绎的特点出发，指出归纳和演绎并不能保证科学知识的确定性。科学的作用就在于提供信仰的同时，给予我们一种怀疑的精神。     

企业诱致性技术创新:原理与实现途径

企业诱致性技术创新的诱因有两个:一是资源稀缺变化所引起的要素相对价格变化;二是增长的产品需求。诱致性技术创新的原理表明其是最有效率的一种技术进步方式,技术引进虽然也是一种技术进步,但是会造成一定的经济效率损失。企业诱致性技术创新实现的条件是竞争的市场环境和制度创新,实现的最重要途径是准确定位政府的职能和破除既得利益集团。     

主导产业双指标体系遴选——以安徽“十二五”主导产业选择为例

工业主导产业的选择与培育对“十二五”安徽经济的发展具有重要现实意义。从安徽工业实际现状出发,在分析主导产业理论和主导产业特征的基础上,建立两套工业主导产业选择指标体系,利用两者选择结果的交集有助于合理分析确定安徽工业的主导产业,并进一步给出培育安徽工业主导产业的政策性建议。