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.     

对当今国际宏观经济政策合作与世界货币体系改革的思考

这次国际金融危机肇始于美国次贷危机,不仅由于美国自身的经济结构及政策失误,还在于国际货币体系中美元的特殊地位。自上世纪30年代大危机后,许多西方国家借助凯恩斯主义的宏观经济管理,得以在数十年间避免了30年代大危机再度袭击。但在经济全球化条件下,各国仅靠自身的宏观经济管理也难以自保,只能靠区域性或全球化的宏观经济政策国际合作。从1985年的广场协议,到今年4月的G20集团的伦敦会议,都是适应经济全球化要求的宏观经济政策国际合作。但这些都在联合国框架之外进行。如果说广场协议意味着对国际金融旧秩序的突破,那么,G20集团伦敦会议则意味着一个新秩序的孕育。     

Credit Derivatives in an Affine Framework

An efficient method for valuing credit derivatives based on three entities is developed in an affine framework. This includes interdependence of market and credit risk, joint credit migration and counterparty default risk of three firms. As an application we provide closed form expressions for the joint distribution of default times, default correlations, and default swap spreads in the presence of counterparty default risk. Vienna Institute of Finance is funded by WWTF (Vienna Science and Technology Fund).     

国家主权信用评级质量检验方法研究

国家主权信用评级对当今国际经济和金融运行有着极为重要的影响力。但是,与其地位不相符的是,评级机构的评级结果事后多次被证明准确性和前瞻性较差。事先缺乏预警而事后大幅降级,甚至对加剧危机起到了推波助澜的作用。本文从国家主权信用评级质量的检验方法入手,系统分析了违约率和迁移率等传统方法在检验评级结果起到的作用及其不足,给出了检验评级质量的一般方法,并验证了该评级检验方法的科学性和准确性。     

Pricing counterparty default risks: Applications to FRNs and vulnerable options

This paper provides simple closed-form pricing models for floating-rate notes and vulnerable options under the counterparty risk framework of [Jarrow, R., Yu, F., 2001. Counterparty risk and the pricing of default risk. Journal of Finance 56, 1765-1799]. After deriving closed-form pricing models for them, this paper illustrates the impact of the default intensity of counterparty on the prices of floating-rate notes and vulnerable options. Numerical examples show that the default risk of counterparty is an important factor of the value of floating-rate notes and vulnerable options.     

Credit risk measurement: Developments over the last 20 years

This paper traces developments in the credit risk measurement literature over the last 20 years. The paper is essentially divided into two parts. In the first part the evolution of the literature on the credit-risk measurement of individual loans and portfolios of loans is traced by way of reference to articles appearing in relevant issues of the Journal of Banking and Finance and other publications. In the second part, a new approach built around a mortality risk framework to measuring the risk and returns on loans and bonds is presented. This model is shown to offer some promise in analyzing the risk-return structures of portfolios of credit-risk exposed debt instruments.     

Selecting credit rating models: a cross-validation-based comparison of discriminatory power

In commercial banking, various statistical models for corporate credit rating have been theoretically promoted and applied to bank-specific credit portfolios. In this paper, we empirically compare and test the performance of a wide range of parametric and nonparametric credit rating model approaches in a statistically coherent way, based on a ‘real-world’ data set. We repetitively (k times) split a large sample of industrial firms’ default data into disjoint training and validation subsamples. For all model types, we estimate k out-of-sample discriminatory power measures, allowing us to compare the models coherently. We observe that more complex and nonparametric approaches, such as random forest, neural networks, and generalized additive models, perform best in-sample. However, comparing k out-of-sample cross-validation results, these models overfit and lose some of their predictive power. Rather than improving discriminatory power, we perceive their major contribution to be their usefulness as diagnostic tools for the selection of rating factors and the development of simpler, parametric models.

基于藤结构Copula的多元信用风险相关性度量模型及其比较

在信贷组合管理的框架下,以行业信用风险为基础,构建了基于藤结构Copula的多元信用风险相关性度量模型,并以2006年6月～2010年12月中国上市公司数据对模型进行了参数估计,发现Canonical藤结构更适合度量行业信用风险相关性,以电力煤气及水的生产为代表的强周期性行业对信用风险起着引导作用.     

Corporate bond default risk: A 150-year perspective

We study corporate bond default rates using an extensive new data set spanning the 1866-2008 period. We find that the corporate bond market has repeatedly suffered clustered default events much worse than those experienced during the Great Depression. For example, during the railroad crisis of 1873-1875, total defaults amounted to 36% of the par value of the entire corporate bond market. Using a regime-switching model, we examine the extent to which default rates can be forecast by financial and macroeconomic variables. We find that stock returns, stock return volatility, and changes in GDP are strong predictors of default rates. Surprisingly, however, credit spreads are not. Over the long term, credit spreads are roughly twice as large as default losses, resulting in an average credit risk premium of about 80 basis points. We also find that credit spreads do not adjust in response to realized default rates.     

Macroeconomic Conditions, Firm Characteristics, and Credit Spreads

We study a structural model that allows us to examine how credit spreads are affected by the interaction of macroeconomic conditions and firm characteristics. Unlike most other structural models, our model explicitly incorporates equilibrium macroeconomic dynamics and models a firm's cash flow as primitive processes. Corporate securities are priced as contingent claims written on cash flows. Default occurs when the firm's cash flow cannot cover the interest payments and the recovery rate is dependent on the economic condition at default. Our model produces the following predictions: (i) credit spread is mostly negatively correlated with interest rate; (ii) credit spread yield curves are upward sloping for low-grade bonds; (iii) firm characteristics have significant effects on credit spreads and these effects also vary with economic conditions. These predictions are consistent with the available empirical evidence and generate implications for further empirical investigation.     

What drives corporate default risk premia? Evidence from the CDS market

This article studies the economic factors behind corporate default risk premia in Europe during the period 2006–2010. We employ information embedded in Credit Default Swap (CDS) contracts to quantify expected excess returns from the underlying bonds in market-wide default circumstances. We disentangle the compensation to investors for unexpected changes in the creditworthiness of the bond issuer from their remuneration for the risk that the bond's price will drop in the event of default. Our results show that the risk premia associated with systematic factors influencing default arrivals represent approximately 40% of total CDS spread (on median). These premia also exhibit a strong source of commonality; a single principal component explains approximately 88% of their joint variability. This factor significantly covaries with aggregate illiquidity and sovereign risk variables. Empirical evidence suggests a public-to-private risk transfer between sovereign credit spread and corporate risk premia. Finally, the compensation in the event of default is approximately 14 basis points of the total CDS spread, and a significant amount of jump-at-default risk may not be diversifiable.