Default risk is the uncertainty surrounding a firm's ability to service its debts and obligations. Prior to default, there is no way to discriminate unambiguously between firms that will default and those that won't. At best we can only make probabilistic assessments of the likelihood of default. As a result, firms generally pay a spread over the default-free rate of interest that is proportion...

Consider a portfolio of n obligors subject to possible default. We propose a new structural model for the loss given default, which takes into account the severity of default. Then we study the tail behavior of the loss given default under the assumption that the losses of the n obligors jointly follow a multivariate regular variation structure. This structure provides an ideal framework for mo...

In this article, a framework for the joint modelling of default and recovery risk in a portfolio of credit risky assets is presented. The model especially accounts for the correlation of defaults on the one hand and correlation of default rates and recovery rates on the other hand. Nested Archimedean copulas are used to model different dependence structures. For the recovery rates a very flexib...

index tracking is the process of developing a portfolio that reproduces the performance of an index. the tracker portfolio has relatively good diversity and low turnover and low transaction costs. in this paper we applied a binary programming model for index tracking problem. in this model the number of assets for portfolio construction is defined by portfolio manager. the robust optimization f...

We propose a fast algorithm for computing the expected tranche loss in the Gaussian factor model with arbitrary accuracy using Hermite expansions. No assumptions about homogeneity of the portfolio are made. The algorithm is a generalization of the algorithm proposed in [4]. The advantage of the new algorithm is that it allows us to achieve higher accuracy in almost the same computational time. ...

A multi-name credit derivative is a security tied to an underlying portfolio of corporate bonds or other credit-sensitive securities. It enables investors to buy and sell protection against the default losses in the portfolio. The value of a multiname derivative depends on the distribution of portfolio loss at multiple horizons. Intensity-based models of the loss point process that are specifie...

We analyze the fluctuation of the loss from default around its large portfolio limit in a class of reduced-form models of correlated firm-by-firm default timing. We prove a weak convergence result for the fluctuation process and use it for developing a conditionally Gaussian approximation to the loss distribution. Numerical results illustrate the accuracy and computational efficiency of the app...

The goal of this paper is to determine the Incremental Risk Charge (IRC) and the Comprehensive Risk Measure (CRM) of a portfolio consisting of credit derivatives and tranches. More specifically, we implement different methods to calibrate default intensity models, backtest our IRC calculations over historical data, and focus our attention on a basket of Credit Default Swaps (CDS).

Modeling correlated default risk is a new phenomenon currently sweeping through the credit markets. Little is known about the drivers of default risk at the portfolio level. This paper develops a methodology to assess alternative specifications of the joint distribution of default risk. Specifications are based on three criteria: level, asymmetry, and tail-dependence in the joint default distri...

In this article, we describe the construction and implementation of a pricing model for a leading UK mortgage lender. The crisis in mortgage lending has highlighted the importance of incorporating default risk into such pricing decisions by mortgage lenders. In this case the underlying default model is based on survival analysis, which allows the estimation of month-to-month default probabiliti...