The granularity principle [Gordy (2003)] allows for closed form expressions of the risk measures of a large portfolio at order 1/n, where n is the portfolio size. The granularity principle yields a decomposition of such risk measures that highlights the different effects of systematic and unsystematic risks. This paper derives the granularity adjustment of the Value-at-Risk (VaR), the Expected ...

In credit scoring, low-default portfolios are those for which very little default history exists. This makes it problematic for financial institutions to estimate a reliable probability of a customer defaulting on a loan. Banking regulation (Basel II Capital Accord), and best practice, however, necessitate an accurate and valid estimate of the probability of default. In this article the suitabi...

We consider the risk of a portfolio comprising loans, bonds, and financial instruments that are subject to possible default. In particular, we are interested in performance measures such as the probability that the portfolio incurs large losses over a fixed time horizon, and the expected excess loss given that large losses are incurred during this horizon. Contrary to the normal copula that is ...

Companies in the same industry sector are usually stronger correlated than firms in different sectors, as they are similarly affected by macroeconomic effects, political decisions, and consumer trends. In spite of many stock return models taking account of this fact there are only a few credit default models taking it into consideration. In this paper we present a default model based on nested ...

In our project we have used parametric simulation and filtered historical simulation by GARCH processes to model the future position on a portfolio of some actively trading S&P bonds and related credit default swaps. The portfolio is marked to market daily based on the daily prices and CDS spreads over a seven year period. The Credit default swaps are priced daily based on the shifts in the def...

Background In consumer lending, portfolio managers typically have access to a scorecard used to forecast default probability for each applicant. Scorecards are built using historical data on loan accounts and their respective performance data. The inputs into the scorecard include financial, demographic and other personal information about each applicant. The output of the scorecard is a real-v...

We propose a portfolio-based solving approach to Answer Set Programming (ASP). Our approach is homogeneous in considering several configurations of the ASP solver clasp. The selection among the configurations is realized via Support Vector Regression. The resulting portfolio-based solver claspfolio regularly outperforms clasp’s default configuration as well as manual tuning.

Default loss distribution of corporate portfolios plays a crucial role in CDO tranche pricing, tracking error calculation and profit/loss assessment of corporation systems. This work gives an efficient algorithm to calculate the default loss distribution based on Hull-White probability bucketing approach and importance sampling method. The Gaussian copula model is assumed to calculate the condi...

In this paper we propose a factor contagion model for correlated defaults. The model covers the heterogeneous conditionally independent portfolio and the factor infectious default portfolio as special cases. The model assumes that the hazard rate processes are driven by external common factors as well as defaults of other names in the portfolio. The total hazard construction method is used to d...