Correlation smile matching for collateralized debt obligation tranches with α-stable distributions and fitted Archimedean copula models

As an extension of the standard Gaussian copula model to price collateralized debt obligation (CDO) tranche swaps we present a generalization of a one-factor copula model based on stable distributions. For special parameter values these distributions coincide with Gaussian or Cauchy distributions, but changing the parameters allows a continuous deformation away from the Gaussian copula. All these factor copulas are embedded in a framework of stochastic correlations. We furthermore generalize the linear dependence in the usual factor approach to a more general Archimedean copula dependence between the individual trigger variable and the common latent factor. Our analysis is carried out on a non-homogeneous correlation structure of the underlying portfolio. CDO tranche market premia, even throughout the correlation crisis in May 2005, can be reproduced by certain models. From a numerical perspective, all these models are simple, since calculations can be reduced to one-dimensional numerical integrals.     

Doing Least Squares: Perspectives from Gauss and Yule

Gauss introduced a procedure for calculating least squares estimates and their precisions. Yule introduced a new system of notation adapted to correlation analysis. This paper describes these formalisms and compares them with the matrix and vector space formalisms used in modern regression analysis.     

对外直接投资与美国服务贸易的发展

一般认为,对外直接投资活动(FDI)对贸易的持续增长将起到十分重要的支撑和推动作用。本文选用了美国1970年至2003年的相关数据,通过建立自回归模型,拟合后发现这个结论在美国的服务业领域也成立。进一步运用Granger因果检验方法,发现两者之间还存在着互为因果的关系。然而,通过对统计数据的分析,同时也直观地发现,在美国服务业内的对外直接投资与对外贸易在进出口上的同向相关性并不明显。其原因可能是各国对服务业的限制措施所造成的扭曲和直接投资的贸易替代效应所致。     

出口机会与进口竞争对工业机器人企业的叠加影响：基于出口持续时间的视角

工业机器人企业是中国推动制造业数字化革命、抢占国际分工制高点战略的主力军,然而其出口持续时间平均不足1年,需引起高度关注。本文基于2000-2015年中国海关数据库和工业企业数据库的匹配数据,运用Cox风险模型分析了出口机会增大和进口竞争加剧对工业机器人企业出口持续时间的影响和作用机制。结果表明,出口机会增大更有利于延长企业出口持续时间,进口竞争加剧则提高了企业的退出率,这一结论在产品多样化程度低、产品核心度低、行业竞争小和市场集中度低的企业中尤为明显;出口机会与进口竞争,主要是通过企业生产率和技术创新的中介作用影响企业的出口持续时间;面对双重叠加影响,工业机器人企业应充分利用产品间的技术关联效应提高出口持续性。     

Sources of time-varying trade balance and real exchange rate dynamics in East Asia

A sticky-price model with minimal assumptions for identification is used to motivate a time-varying model that allows for state dependent innovations to explore the trade balance dynamics of a group of East Asian economies. This paper shows that the correlation between the trade balance and the real exchange has historically been highly conditional on the type of macroeconomic shock. Permanent (transitory) shocks have historically produced a positive (negative) correlation between the trade balance and real exchange rate over the last 20 years. Second, since the Asian financial crisis the real exchange rate dynamics of the East Asian countries have been dominated by persistent component(s), while the dynamics of the trade balance have been more influenced by transitory factors.     

When do improved covariance matrix estimators enhance portfolio optimization? An empirical comparative study of nine estimators

The use of improved covariance matrix estimators as an alternative to the sample estimator is considered an important approach for enhancing portfolio optimization. Here we empirically compare the performance of nine improved covariance estimation procedures using daily returns of 90 highly capitalized US stocks for the period 1997–2007. We find that the usefulness of covariance matrix estimators strongly depends on the ratio between the estimation period T and the number of stocks N, on the presence or absence of short selling, and on the performance metric considered. When short selling is allowed, several estimation methods achieve a realized risk that is significantly smaller than that obtained with the sample covariance method. This is particularly true when T/N is close to one. Moreover, many estimators reduce the fraction of negative portfolio weights, while little improvement is achieved in the degree of diversification. On the contrary, when short selling is not allowed and T?>?N, the considered methods are unable to outperform the sample covariance in terms of realized risk, but can give much more diversified portfolios than that obtained with the sample covariance. When T?<?N, the use of the sample covariance matrix and of the pseudo-inverse gives portfolios with very poor performance.     

一种混沌密码序列的产生及其改进

尝试用数字滤波器产生混沌密码序列 ,针对已有算法和它的一些改进算法存在内部状态间具有较强相关性的问题 ,提出了一种新的改进方法 ,通过合理选择系数 ,产生了效果较好的混沌密码序列     

Econometric modelling in finance and risk management: An overview

This paper gives an overview about the sixteen papers included in this special issue. The papers in this special issue cover a wide range of topics. Such topics include discussing a class of tests for correlation, estimation of realized volatility, modeling time series and continuous-time models with long-range dependence, estimation and specification testing of time series models, estimation in a factor model with high-dimensional problems, finite-sample examination of quasi-maximum likelihood estimation in an autoregressive conditional duration model, and estimation in a dynamic additive quantile model.     

中国系统重要性银行评估：来自2006-2010年中国上市银行的证据

系统重要性银行是指具有负外部性特征,并且由于规模、复杂度与系统相关度在金融市场中承担了关键功能,其无序破产可能给金融体系造成包括核心金融功能的中断、金融服务成本急剧增加等在内的系统性风险,进而可能危及金融稳定、损害实体经济的银行。通过对系统重要性银行进行评估,得出其主要影响指标包括银行规模、关联性、复杂性和可替代性,其中,交易性金融资产与负债是最重要的关联性指标,衍生金融资产与负债是最重要的复杂性指标。系统重要性银行评估结果显示,假定阀值为5%,则全部国有商业银行和股份制商业银行中的招商银行、光大银行和中信银行属于系统重要性银行,而其他股份制商业银行和全部城市商业银行则不属于系统重要性银行。