LOG-PERIODOGRAM ESTIMATION OF LONG MEMORY VOLATILITY DEPENDENCIES WITH CONDITIONALLY HEAVY TAILED RETURNS

Many recent papers have used semiparametric methods, especially the log-periodogram regression, to detect and estimate long memory in the volatility of asset returns. In these papers, the volatility is proxied by measures such as squared, log-squared, and absolute returns. While the evidence for the existence of long memory is strong using any of these measures, the actual long memory parameter estimates can be sensitive to which measure is used. In Monte-Carlo simulations, I find that if the data is conditionally leptokurtic, the log-periodogram regression estimator using squared returns has a large downward bias, which is avoided by using other volatility measures. In United States stock return data, I find that squared returns give much lower estimates of the long memory parameter than the alternative volatility measures, which is consistent with the simulation results. I conclude that researchers should avoid using the squared returns in the semiparametric estimation of long memory volatility dependencies.     

见义不为现象的法律救治

见义勇为立法的重要内容之一,就是规定社会和国家对见义勇为者权益的救济和保护负有不可推卸的义务。作者认为对见义勇为者的权益实行法律保护是救治当前道德冷漠现象的一剂良方,是与现实需要紧密结合的法律规范。它的制定与实施又进一步充实了法律的正义精神,是法律价值的全面体现。但在现阶段我国还不具备相应的历史与现实条件用法律强制的手段推行见义勇为的道德行为。     

区域经济一体化对世界福利及多边贸易体制的影响

随着经济的全球化,在以GATT和WTO为代表的多边贸易自由化不断深化的同时,区域经济一体化组织层出不穷。而区域经济一体化对于世界福利和多边贸易是有利有弊的。因此,在政策制定上要扬长避短,既限制其不利的影响,同时又要积极发挥它的积极作用。     

Do Lets Work?

This study aims to uncover some of the reasons for differences in attitudes towards family‐friendly and equal opportunities (EO) policies for women between senior and junior staff and between male and female staff. This in‐depth case study of a multi‐national corporation in Hong Kong that included a survey questionnaire, interviews and participant observation suggests four categories of female employees according to their approach to EO: advocators, supporters, outsiders and rejecters. The approach adopted was dependent on the woman's level of empathy towards the situation of working women and the extent of her career ambition. Four categories of male employees can also be classified depending on their level of empathy towards women's situation (similar to women's case) and their extent of career satisfaction (in contrast to women's career ambition), namely, antagonists, outsiders, fence‐sitters and sympathizers. Women at higher levels were less supportive of EO than women at lower levels. No such clear relationship between organizational level and attitudes towards EO was observed among men. In Hong Kong, female managers had little expectation that their organization would be family‐friendly and women workers who consciously chose to balance work and family accepted that it meant fewer promotional chances. No such self‐adjusted depressed ambition was observed among men.     

基于可达性的用户最优动态交通配流模型研究

以多种已有模型为基础，建立了动态配流流量细化原则，并依据这一原则，在避免估算路段走行时间的情况下构造了一个改进的新模型．该模型的解释性强，具有全局收敛性，并考虑了距离不同带来的可达性的影响．在对该模型最优解条件的充要性进行说明的同时，对新模型的择路机理也予以了推证．     

体验、解析、会通——张岱年哲学方法论的综合创新

体验、解析、会通的有机统一,是张岱年《天人五论》所建构的哲学方法论。这种方法论排斥直觉法,因而不同于现代新儒家和清华学派的哲学家;同时,它把辩证法看成一般的学术方法而非独立的哲学方法,这又使其不同于当时的新唯物论者。这种方法论是在综合中西哲学方法以及近现代各派哲学方法基础上的一个综合创造。     

女性"隐形"地位的多元认知透视

在男性占主导地位的语言,诚如英汉语中"乞丐""医生"等职业术语和"chairman""hero"等官衔荣誉称呼之类的名词,一般性的人类泛指"a man","mankind"以及代词的非指示用法中,女性往往被置于"隐形"的地位。性别差异和性别歧视的现象已引起社会上各学科的普遍关注,然而,从认知角度对这一现象作出注解的文章寥寥。运用认知语言学中的原型和范畴理论、框架理论、心理空间和概念合成理论对此予以阐释,可为英汉语中这一现象的理论阐释提供全新的多元认知视角。     

Quality strategies in supply chain alliances of disposable items

This paper studies a single-product distribution channel where a supplier manufactures items of a given type, some of which are defective, that are sold by a retailer who only detects a subset of the defective items, passing the rest along to customers. We conjecture the structure of the demand and cost functions, assuming customers to have a decreasing marginal aversion to bad quality while both the supplier and the retailer make marginally increasing efforts to avoid bad quality. This allows us to deduce several implicit parameters of a cost model based on observable data, such as the share of the channel margin. Once the parameters of the model are available, we analyze the result of vertical integration. Although we confirm the well-known fact that vertical integration improves the quality perceived by the customer, we characterize the supplier's decision of whether or not to provide a better quality in terms of the individual channel margins. As an alternative, we derive the conditions under which the supplier and the retailer may devise a mutually beneficial transfer contract that simultaneously increases their profit and improves quality.     

Costs and Rewards of Children: The Effects of Becoming a Parent on Adults' Lives

How do new parents differ from their childless counterparts in social and psychological resources, daily strains, and psychological well‐being? Using a nationally representative panel of 1,933 adults who were childless at the first interview, we compare 6 indicators of adults' lives for those who became parents and those remaining childless several years later, controlling for earlier states. Becoming a parent is both detrimental and rewarding. With the exception of social integration, which is greater for all groups of new parents compared with their childless counterparts, the effects of parental status on adults' lives vary markedly by gender and marital status. Unmarried parents report lower self‐efficacy and higher depression than their childless counterparts. Married mothers' lives are marked by more housework and more marital conflict but less depression than their childless counterparts. Parental status has little influence on the lives of married men.     

产品创新中管理集成平台的分析与设计

管理集成是产品创新管理的发展趋势之一。管理集成平台是复杂产品创新中管理集成实施的重要支撑技术。从管理集成平台的功能和构成出发,设计了一个管理集成平台的一般模型,它具有对外部环境变化的快速反应功能,能正确规划产品开发过程的有关资源,从而有利于提高产品创新管理。