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.     

Marital Conflict,Ineffective Parenting,and Children's and Adolescents' Maladjustment

Data from the 1988 National Survey on Families and Households were analyzed to examine the associations among marital conflict, ineffective parenting, and children's and adolescents' maladjustment. Parents' use of harsh discipline and low parental involvement helped explain the connection between marital conflict and children's maladjustment in children aged 2 through 11. Parent‐child conflict was measured only in families with a target teenager and also was a significant mediator. Although ineffective parenting explained part of the association between marital conflict and children's maladjustment, independent effects of marital conflict remained in families with target children aged 2 through 11 (but not for families with a teenager). With a few exceptions, this pattern of findings was consistent for mothers' and fathers' reports, for daughters and sons, for families with various ethnic backgrounds, and for families living in and out of poverty.     

Conditional Likelihood Estimators for Hidden Markov Models and Stochastic Volatility Models

ABSTRACT.  This paper develops a new contrast process for parametric inference of general hidden Markov models, when the hidden chain has a non-compact state space. This contrast is based on the conditional likelihood approach, often used for ARCH-type models. We prove the strong consistency of the conditional likelihood estimators under appropriate conditions. The method is applied to the Kalman filter (for which this contrast and the exact likelihood lead to asymptotically equivalent estimators) and to the discretely observed stochastic volatility models.     

B股与H股及红筹股之间的溢出效应与信息流动

运用向量GARCH-M模型检验了B股与H股及红筹股之间的溢出效应与信息流动.实证结果表明:红筹股对沪深市B股、H股对沪市B股的收益和波动溢出效应均显著存在,而反向的溢出效应均不显著,表明信息是从红筹股向沪深市B股、从H股向沪市B股单向流动的;深市B股与H股之间相互的收益溢出效应均存在,而波动溢出效应均不存在,信息在H股和深市B股之间的流动情况不明显;在信息流动过程中,红筹股始终处于信息领先地位.     

股市联动中的“涟漪效应”

本文提出"涟漪效应"来解释国际股市联动性的大幅波动。所谓涟漪效应就是中心市场特有波动对其它市场间联动性产生影响的现象。本文采用滚动窗口和DCC-GARCH的方法计算了市场特有波动和收益相关系数,以9个主要市场指数为样本对国际股票市场中涟漪效应进行实证检验。研究结果显示,2007年后国际股市联动性变化与美国市场的涟漪效应有关,美国市场特有波动升高（降低）会导致全球股市联动性升高（降低）,而其他市场特有波动并没有类似影响。美国市场与其他市场间联动性基本不受第三方市场特有波动的影响,A股与美股联动性的增强是造成A股与其它股市联动性变化的主要原因。此外,研究特有波动与相关系数的关系能帮助我们识别国际股市中风险传递方向,本文结果显示欧洲市场对其他市场的影响非常有限,以往研究可能高估了欧洲市场的影响力。本文丰富了股市联动性影响因素的研究,对理解市场联动性变化、评估市场影响力等问题有重要意义。     

金融市场多标度分形现象及与风险管理的关系

已有研究通过对汇率、股票收益率、黄金价格等金融市场实证数据的分析,发现这些数据 具有多标度分形(multifractal) 特征. 通过对中国金融市场的代表数据之一———上海证券交易 所综合股价指数(SSECI) 的研究得出了相似的结论,并且初步提出了运用多标度分形理论所 提供的信息来进行金融风险管理的风险管理思路.     

金融工程中资产收益的连续时间模型评述

总结了在过去30年中金融资产收益连续时间模型的发展及主要成果,讨论了迄今连续时间模型参数估计的主要方法,其中特别讨论了MCMC方法;最后指出了现在和未来该领域研究所面临的主要课题。     

基于GARCH族模型的深证成指波动特征实证分析

采用GARCH族模型对深证成指总体及分阶段收益率的波动性进行统计拟合分析,指出深证成指的波动具有集聚性、持久性、显著的非对称性效应及阶段性特征。以深证成指价格达到最高点的时间点为分界,将整个样本分成两个阶段:在第一阶段,“利好消息”对深证成指的冲击比同等程度的“利空消息”大;在第二阶段,“利空消息”的冲击比同等程度的“利好消息”大。这说明深证市场具有杠杆效应。     

中间品贸易视角下的国际研发合作行为研究

随着全球化程度加深,与国外企业进行研发合作逐步成为国内企业参与创新驱动发展战略的重要途径.从中间品贸易视角出发,通过构建谈判博弈模型,分析探讨影响产业链下游企业进行国际研发合作内生性选择的因素.研究发现,只有在研发溢出效应比较小的时候,产业链下游企业才会选择进行国际研发合作.但如果研发溢出效应过小,下游企业的国际研发合作行为会导致本国社会福利水平下降.进一步研究发现,上游市场垄断势力增强以及最终品贸易成本下降均会对产业链下游企业的国际研发合作产生促进作用.