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.     

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.     

从战争和改革的视角看英国民族国家形成的历程

民族国家是以民族为基础而建立的主权国家,国家主权和民族一体性是其建立的两个必备要素。英国民族国家的形成经历了漫长的历程,14、15世纪,英吉利民族经历了百年战争和玫瑰战争的动荡,萌生了一种强烈的民族意识,王权逐渐战胜封建割据势力,民族国家建立的条件日益具备;16世纪,经过宗教改革和政府改革,王权得以最终摆脱教皇控制,国家机构进一步完善,英国民族国家最终形成。     

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。     

欧洲一体化进程中的社会福利整合

欧洲一体化是一个经济、政治和文化不断融合的过程。欧盟从建立之初就开始了劳工政策领域的合作,随着区域经济合作加强、移民增加、劳动力市场一体化,各国社会保障制度之间的差异就成了迫切需要解决的问题。社会保障方面的合作越来越受到重视,合作的范围逐渐扩大到促进就业、失业保障、养老保障、医疗和公共卫生等领域,虽然至今还没有欧盟统一层面的社会保障政策出台,但在某些方面已经出现了趋同倾向。