Technical paper/Credit risk
A multi-state Vasicek model for correlated default rate and loss severity
Correlation between default and recovery has an important bearing on credit risk capital. Here, Rahul Sen shows that the effect can be modelled efficiently by allowing multiple loss states in the Vasicek framework. Heavy-tailed distributions result for…
Confidence intervals for corporate default rates
Rating agency default studies provide estimates of mean default rates over multiple time horizons but have never included estimates of the standard errors of the estimates. This is due, at least in part, to the challenge of accounting for the high degree…
Confidence intervals for corporate default rates
Rating agency default studies provide estimates of mean default rates over multiple time horizons but have never included estimates of the standard errors of the estimates. This is due at least in part to the challenge of accounting for the high degree…
Uncovering PD/LGD liaisons
Francisco Sanchez, Roland Ordovas, Elena Martinez and Manuel Vega consider the presence of correlation between default and recovery through the familiar variance of loss formula. Business cycle dependence permits a neat decomposition of the variance…
Calibration of PD term structures: to be Markov or not to be
A common discussion in credit risk modelling is the question of whether term structures of default probabilities can be satisfactorily modelled by Markov chain techniques. Christian Bluhm and Ludger Overbeck show that empirical multi-year default…
The underlying dynamics of credit correlations
Research Papers
Loan portfolio value
Using a conditional independence framework, Oldrich Vasicek derives a useful limiting form for the portfolio loss distribution with a single systematic factor. He then derives a risk-neutral distribution suitable for traded portfolios, and shows how…