内部评级违约概率度量模型的演进与启示

违约概率度量是巴塞尔新资本协议内部评级法的核心内容之一.按照其不断演进的内在逻辑,对国外主要的违约概率度量模型进行了全面的分析与评价,对国内建立或选择合适的违约概率度量模型具有重要的启示意义.     

The Impact of Owner’s Identity on Banks’ Capital Adequacy and Liquidity Risk

In this article, we test the potential impact of the owner’s identity on banks’ capital adequacy and liquidity risk as defined by the Basel III regulatory framework. Using a unique dataset on a sample of banks domiciled in the Middle East and North Africa region, we find that the ownership structure is an important driver of banks’ regulatory capital and liquidity risk. Private and foreign investors exhibit a stronger preference for higher levels of capital, whereas the impact of government ownership on banks’ risk remains inconclusive. Moreover, privately-owned banks evidenced lower levels of liquidity risk compared to the other groups during the last financial crisis because of tighter budget constraints and more compelling liquidity needs.     

Skewness of Returns, Capital Adequacy, and Mortgage Lending

We calibrate a simulation model of credit value-at-risk for mortgage lending to UK experience. Simulations to capture the skewness of returns that might arise in the context of a financial crisis suggest that the IRB calculations of the new Basel Accord can substantially understate prudential capital adequacy. The same model shows that raising capital requirements has only a small impact on bank funding costs. We conclude that Pillar 2 supervisory review should increase capital requirements above IRB levels for secured bank assets—those whose returns can potentially fall furthest, relative to other, normally “riskier” assets, in extreme outcomes. JEL classification: G21, G28, R31. Presented at the December 2003 conference at the University of Tor Vegata, Rome. We are grateful for comments from William Lang, Mario Onarato, Larry Wall, and from an anonymous referee. All errors and omissions are our own responsibility. “The lady doth protest too much, methinks. The Queen's response to the players in Hamlet, Act 3, scene 2.     

Predicting loss given default (LGD) for residential mortgage loans: A two-stage model and empirical evidence for UK bank data

With the implementation of the Basel II regulatory framework, it became increasingly important for financial institutions to develop accurate loss models. This work investigates the loss given default (LGD) of mortgage loans using a large set of recovery data of residential mortgage defaults from a major UK bank. A Probability of Repossession Model and a Haircut Model are developed and then combined to give an expected loss percentage. We find that the Probability of Repossession Model should consist of more than just the commonly used loan-to-value ratio, and that the estimation of LGD benefits from the Haircut Model, which predicts the discount which the sale price of a repossessed property may undergo. This two-stage LGD model is shown to perform better than a single-stage LGD model (which models LGD directly from loan and collateral characteristics), as it achieves a better R² value and matches the distribution of the observed LGD more accurately.     

中资银行引进境外战略投资者效应的案例研究

在中资银行战略引资步伐加快、外资话语权逐步提升的情况下,本文通过对美国新桥投资集团控股深圳发展银行案例的分析,对外资话语权的提升与中资银行的经营绩效之间的关系进行了探讨。研究发现,外资话语权的提升与中资银行的盈利能力和经营效率之间不存在明显的正相关关系,而外资充分的话语权有助于中资银行防范与化解信贷风险和增强抵御风险能力以及提高业务发展能力;另一方面,外资话语权的提升却与中资银行的业务创新能力呈现负相关的关系。在此基础上,本文提出了有关战略引资的建议。     

Approximation of aggregate and extremal losses within the very heavy tails framework

The loss distribution approach is one of the three advanced measurement approaches to the Pillar I modeling proposed by Basel II in 2001. In this paper, one possible approximation of the aggregate and maximum loss distribution in the extremely low frequency/high severity case is given, i.e. the case of infinite mean of the loss sizes and loss inter-arrival times. In this study, independent but not identically distributed losses are considered. The minimum loss amount is considered increasing over time. A Monte Carlo simulation algorithm is presented and several quantiles are estimated. The same approximation is used for modeling the maximum and aggregate worldwide economy losses caused by very rare and very extreme events such as 9/11, the Russian rouble crisis, and the U.S. subprime mortgage crisis. The model parameters are fit on a data sample of operational losses. The respective aggregate and extremal loss quantiles are calculated.     

商业银行资本缓冲水平的决定因素——基于我国上市银行的实证分析

文章使用动态面板数据对我国13家上市银行2000年至2010年间持有的资本缓冲水平与经济周期、资本收益率、资产风险水平和资产规模之间的关系进行实证分析。结果表明我国上市银行的资本缓冲水平与经济周期和银行规模之间存在显著的正相关关系,此外资本缓冲水平还受到资本调整成本、资本收益率和资产质量的显著影响。最后在实证分析的基础上为我国银行监管部门如何落实《巴塞尔协议Ⅲ》的资本缓冲要求提出政策建议。     

风险度量的幻觉与基于模型的银行资本监管方法

《巴塞尔协议Ⅲ》将新资本协议的缺陷,看成是可以通过提高资本充足标准来改进的缺陷,没有系统地分析现有银行监管模式中所存在的问题。文章分析了风险度量模型所存在的一些内在缺陷,并指出,巴塞尔银行监管模式的基本假设——金融风险可以通过先进模型来准确度量,其实只是一种幻觉。文章同时指出,如果模型不能准确地度量风险,在现有的基于模型的银行监管模式下,更高的资本充足要求,只会激起银行更大的监管套利动机;更为重要的是,这种银行监管模式容易引发内生性风险,从而危及整个系统的稳健性。因此,在提高核心资本标准的同时,巴塞尔委员会应考虑如何更加科学地对银行实施资本充足监管。     

巴塞尔Ⅲ在监管理论与框架上的改进:微观与宏观审慎有机结合

巴塞尔Ⅲ作为此次国际金融危机后全球金融改革的重要成果,不但改进了传统金融监管理论只专注于单个金融机构风险而忽视了系统性风险的不足,而且在监管框架设计上,既注重加强微观审慎监管,又注重宏观审慎监管的有机结合。本文从阐释推动这次全球金融监管改革的理论基础出发,深入剖析了巴塞尔Ⅲ在微观审慎监管和宏观审慎监管上改进的原因与具体进展,最后探讨了巴塞尔Ⅲ可能对中国银行业的影响并提出对中国银行业改革的建议。     

商业银行监管资本套利的动因、模式与影响研究

监管资本套利产生于巴塞尔协议资本监管框架的缺陷,作为巴塞尔协议一个未曾预料的结果,在西方发达国家发展非常迅速。本文回答了三个逐层递进的问题:商业银行是否会进行监管资本套利?商业银行如何进行监管资本套利?商业银行进行监管资本套利会给经济带来怎样的影响?最后依据结论的政策含义,向监管部门提出了相应的参考建议。