Working Papers in Economics,
University of Gothenburg, Department of Economics

Abstract: We study default contagion in large homogeneous credit portfolios. Using data from the iTraxx Europe series, two synthetic CDO portfolios are calibrated against their tranche spreads, index CDS spreads and average CDS spreads, all with five year maturity. After the calibrations, which render perfect fits, we investigate the implied expected ordered defaults times, implied default correlations, and implied multivariate default and survival distributions, both for ordered and unordered default times. Many of the numerical results differ substantially from the corresponding quantities in a smaller inhomogeneous CDS portfolio. Furthermore, the studies indicate that market CDO spreads imply extreme default clustering in upper tranches. The default contagion is introduced by letting individual intensities jump when other defaults occur, but be constant between defaults. The model is translated into a Markov jump process. Expressions for the investigated quantities are derived by using matrix-analytic methods.

Keywords: Credit risk; intensity-based models; dependence modelling; default contagion; Markov jump processes; Matrix-analytic methods; synthetic CDO-s; index CDS-s

JEL-codes: C02; C63; G13; G32; G33

25 pages, October 31, 2007

Download statistics

• University of Gothenburg, Department of Economics
• Ordering Working Papers
• Home page for this series

Questions (including download problems) about the papers in this series should be directed to Jessica Oscarsson ()
Report other problems with accessing this service to Sune Karlsson ().

RePEc:hhs:gunwpe:0272This page generated on 2024-11-14 18:33:26.