Estimating Default Probabilities Implicit in Commercial Mortgage Backed Securities (CMBS)

This paper uses a structural credit risk model, providing an analytical formula to estimate default probabilities implicit in commercial mortgage backed security prices. Empirical studies of CMBS default have focused on the probability of default depending on loan characteristics at the origination and market indices. Recent studies show that unobservable current loan-to-value (LTV) ratio is a key state variable driving default. We update this variable using Real Estate Investment Trust (REIT) property-type indices over time. Later, we employ first passage time approach to study CMBS default using implied LTV.

德国公司违约概率预测及其对我国信用风险管理的启示

内部信用评级是新巴塞尔资本协议的核心,而违约概率的预测又是内部评级的基础。本文利用具有出色分类功能的非线性支持向量分类(SVC)方法来预测德国公司的违约概率,识别其信用风险。结果显示,SVC模型的预测能力优于基准的logit模型;而且非线性SVC模型能够捕捉线性logit模型所不能识别的影响信用风险的重要变量。本文虽然分析的是德国公司数据,但是同样对我国商业银行和公司构建全面风险管理体系有着直接的指导意义。     

An Empirical Comparison of Credit Spreads between the Bond Market and the Credit Default Swap Market

This paper compares the pricing of credit risk in the bond market and the fast-growing credit default swap (CDS) market. The cointegration test confirms that the theoretical parity relationship between the two credit spreads holds as a long-run equilibrium condition. Nevertheless, substantial deviation from the parity can arise in the short run. The panel data study and the VECM analysis both suggest that the deviation is largely due to the higher responsiveness of CDS premia to changes in credit conditions. Moreover, it exhibits a certain degree of persistence in that only 10% of price discrepancies can be removed within a business day.     

Counterparty Risk for Credit Default Swaps: Markov Chain Interacting Intensities Model with Stochastic Intensity

We analyze the counterparty risk for credit default swaps using the Markov chain model of portfolio credit risk of multiple obligors with interacting default intensity processes. The default correlation between the protection seller and underlying entity is modeled by an increment in default intensity upon the occurrence of an external shock event. The arrival of the shock event is a Cox process whose stochastic intensity is assumed to follow an affine diffusion process with jumps. We examine how the correlated default risks between the protection seller and the underlying entity may affect the credit default premium in a credit default swap.     

A Model of Return Volatility with Application to Estimating Relative Risk Aversion

We estimate a monthly return volatility model that allows for the abrupt changes in volatility often observed in returns data. Using this model we are able to identify key months likely to correspond to draws from a high volatility regime. Using our model in conjunction with Merton's (1980) model relating expected risk premia to risk we obtain reasonable estimates of the coefficient of relative risk aversion.     

小企业贷款的信用风险与化解策略

作为小企业间接融资的首选渠道,商业银行在其中扮演着非常重要的角色。然而小企业贷款对于商业银行而言,存在风险高、成本高、效率低、收益低的现象。文章对小企业存在的信用风险进行了分析,并提出了政策建议。     

对农村信用社发展社团贷款的实践与思考

面对竞争压力,如何拓展业务、增加盈利,对于目前的农信社来说,无疑也和对体制的改革一样重要。在这一背景下,农信社应通过加强社与社之间的合作,培育和开发社团贷款市场,使其逐渐发展成为农信社极具竞争力和盈利能力的核心业务之一。     

我国农林牧渔业短期贷款企业违约判别实证分析

近几年，我国农林牧渔业短期贷款企业的违约严重程度一直居所有行业之首，从跨行业的角度评估该行业短期贷款企业的违约具有重要意义。本文基于全国跨银行的贷款企业海量数据库样本，针对农林牧渔业的短期贷款企业进行了分规模和分地区样本的多元判别分析模型、Logistic模型与神经网络模型等的构建与实证探索，进而找出了影响我国农林牧渔业企业违约的关键变量，构建了最佳违约判别模型。这些关键变量和判别模型对中国人民银行和各商业银行监测该行业企业的信用风险具有重要的参考价值。     

The Sensitivity of the Loss Given Default Rate to Systematic Risk: New Empirical Evidence on Bank Loans

We verify the existence of a relation between loss given default rate (LGDR) and macroeconomic conditions by examining 11,649 bank loans concerning the Italian market. Using both the univariate and multivariate analyses, we pinpoint diverse macroeconomic explanatory variables for LGDR on loans to households and SMEs. For households, LGDR is more sensitive to the default-to-loan ratio, the unemployment rate, and household consumption. For SMEs, LGDR is influenced by the total number of employed people and the GDP growth rate. These findings corroborate the Basel Committee’s provision that LGDR quantification process must identify distinct downturn conditions for each supervisory asset class.

信用违约风险传染模型的比较研究

本文试图对几种有代表性的模型进行比较,来分析由于建模方式的不同,而导致的对信用期权定价和对冲的结果的不同.如果将违约风险传染考虑进去,类似德隆帝国崩溃的事件,或许就能避免.     

主权信用违约互换的运作及启示

欧洲各国主权债务危机的频发,使得主权CDS在全球范围内备受瞩目。本文分析了主权CDS的市场发展状况、运作及定价机制;考察欧洲主权债务危机中主权CDS的行为;提出对我国地方政府债务问题的启示。研究发现:(1)主权CDS息差变化受到了欧元区因素、本国因素、投机和代理对冲的影响;(2)短期主权CDS供不应求;(3)禁止主权CDS的裸卖空交易存在不合理性;(4)西欧主权风险外溢使得东欧及新兴市场国家的主权CDS市场波动加剧。     

Cyclical correlations, credit contagion, and portfolio losses

We model aggregate credit losses on large portfolios of financial positions contracted with firms subject to both cyclical default correlation and direct default contagion processes. Cyclical correlation is due to the dependence of firms on common economic factors. Contagion is associated with the local interaction of firms with their business partners. We provide an explicit normal approximation of the distribution of portfolio losses. We quantify the relation between the variability of global economic fundamentals, strength of local firm interaction, and the fluctuation of losses. We find that cyclical oscillations in fundamentals dominate average losses, while local interaction causes additional fluctuations of losses around their average. The strength of the contagion-induced loss variability depends on the complexity of the business partner network.     

经济波动、不良贷款与银行业系统性风险

在全球经济变动及宏观经济不确定性增强的背景下,中国经济波动的信贷周期及银行亲周期性的双重特征极易触发银行业的系统性风险。本文以经济波动与不良贷款的关系为切入点,采用时间序列分析方法系统地研究了上述问题并证明了二者之间的因果关系。基于研究结论,本文提出了研究、评估经济波动对银行业的潜在影响、审慎使用信用风险模型、实施差别化的调控政策、推进银行战略转型等政策建议,以有效预防银行业的系统性风险。     

Credit Risk and the Term Structure of Lease Rates: A Reduced Form Approach

Previous research either assumes default free leases or leases subject to default risk using a structural approach. However, structural credit risk models suffer from a common criticism that the firm’s asset value process is unobservable. We develop a reduced form credit risk model for leases that avoids making assumptions regarding unobservable asset valuation processes. Furthermore, we assume a correlated market and credit risk that provides us with a simple analytic formula for valuing defaultable lease contracts. Numerical analysis reveals that tenant credit risk can have a substantial impact on the term structure of leases. Finally, we use the model to demonstrate the implied lease term structure for a set of retail and financial firms in the Fall of 2000.

商业银行公司贷款中的隐含V形期权与潜在的中国信贷风险

本文提出一种V形期权模型,并以此来刻画中国商业银行公司贷款业务中隐含的借款人套利风险.借助于该模型,本文分析了宏观环境变化威胁商业银行公司贷款质量的一种路径,探讨了商业银行现有风险量化手段的不足.结合当前的世界经济状况和中国信贷环境中的问题,本文认为中国存在由此引发金融风险的可能,并提出了规避或减轻此类风险的建议.     

Credit ratings and the cross-section of stock returns

Low credit risk firms realize higher returns than high credit risk firms. This is puzzling because investors seem to pay a premium for bearing credit risk. The credit risk effect manifests itself due to the poor performance of low-rated stocks (which account for 4.2% of total market capitalization) during periods of financial distress. Around rating downgrades, low-rated firms experience considerable negative returns amid strong institutional selling, whereas returns do not differ across credit risk groups in stable or improving credit conditions. The evidence for the credit risk effect points towards mispricing generated by retail investors and sustained by illiquidity and short sell constraints.     

Interacting default intensity with a hidden Markov process

In this paper we consider a reduced-form intensity-based credit risk model with a hidden Markov state process. A filtering method is proposed for extracting the underlying state given the observation processes. The method can be applied to a wide range of problems. Based on this model, we derive the joint distribution of multiple default times without imposing stringent assumptions on the form of default intensities. Closed-form formulas for the distribution of default times are obtained which are then applied to solve a number of practical problems such as hedging and pricing credit derivatives. The method and numerical algorithms presented can be applicable to various forms of default intensities.     

抵押风险分析和抵押贷款违约损失率研究

违约损失率是BaselⅡ规定的六大风险指标之一,而抵押是BaselⅡ标准法规定的信用风险缓释工具之一,两者在巴塞尔新资本协议中有着非常关键的地位和作用.本文总结了国内外违约损失率的研究概况,在利用历史数据对我国商业银行抵押贷款的违约损失率进行实证分析后发现：（1）回收率同融资金额成反比;（2）回收率同融资折率成反比;（3）回收率呈“U”型分布.本文的分析有助于进一步探究我国商业银行抵押贷款违约损失率的特征,是量化风险暴露和计算监管资本的基础,并为我们下一步的折率研究做好了铺垫.     

Valuation of Residential Mortgage-Backed Securities with Default Risk Using an Intensity-Based Approach

This paper develops a valuation model for fixed-rate mortgages, mortgage pools, and residential mortgage-backed securities (RMBS's) using an intensity-based approach. This model incorporates full prepayment, partial prepayment, and default in valuing a mortgage. Full prepayment is further classified into “refinancing” and “sale of a house” depending on the reason. The time of occurrence of each of these three types of prepayment and default is modeled as the first jump time of a Cox process. Under these conditions, the valuation formula for a mortgage as well as a partial differential equation (PDE) that the mortgage value satisfies is provided. As for implementation of the model, the short-term riskless interest rate and the house price are adopted as state variables. Each intensity process is specified in a manner that allows a jump in intensity depending on the state variables and the borrower's incentive for prepayment or default. Through such specifications, it is shown that our model has characteristics similar to some structural models in previous literature. As for the numerical method for valuation, we propose a simple backward induction technique on a tree instead of the commonly used Monte Carlo method. Additionally, the method for estimating the model is discussed, and the results of numerical simulations are reported.This paper represents the view of the author and does note necessarily the views of the Mitsubishi UFJ Securities Co., Ltd. or members of its staff.