Technical paper/Expected shortfall
An analytical framework for credit portfolio risk measures
An analytical framework for credit portfolio risk measures
Confidence in controlling risk measures
Insurers increasingly use stochastic simulation approaches for estimating risk capital, but numerical errors are rarely measured. A control variate method can improve the accuracy dramatically without increasing the number of simulations.
Shortfall factor contributions
Shortfall factor contributions
Shortfall: who contributes and how much?
Understanding risk contributions is a key part of successful risk management and portfolio optimisation. Richard Martin extends the discussion from value-at-risk to expected shortfall and shows that saddlepoint approximation preserves the convexity…
Risk contributions from generic user-defined factors
In this article, Attilio Meucci draws on regression analysis to decompose volatility, value-at-risk and expected shortfall into arbitrary combinations or aggregations of risk factors, and presents a simple recipe to implement this approach in practice
Shortfall: a tail of two parts
Richard Martin and Dirk Tasche show that the expected shortfall, when used in the conditional independence framework, has an elegant decomposition into systematic (risk-factor-driven) and unsystematic parts. The theory is compared and contrasted with the…
Modelling counterparty credit exposure for credit default swaps
Modelling counterparty credit exposure for credit derivatives is more complicated than for non-credit products, since the reference credit and counterparty can exhibit positive default correlation. Here, Christian Hille, John Ring and Hideki Shimamoto…
Sensible and efficient capital allocation for credit portfolios
Michael Kalkbrener, Hans Lotter and Ludger Overbeck construct a new approach to economiccapital allocation, showing that three axioms uniquely determine a capital allocation scheme,and, more importantly, that any allocation satisfying the axioms is…
Using the grouped t-copula
Student-t copula models are popular, but can be over-simplistic when used to describe credit portfolios where the risk factors are numerous or dissimilar. Here, Stéphane Daul, Enrico De Giorgi, Filip Lindskog and Alexander McNeil construct a new,…
Contributions to credit risk
Optimisation of credit portfolios requires that risk contributions be quantified. However, there has been disagreement over which of three popular tail risk measures should be used. Here, Alexandre Kurth and Dirk Tasche offer a way forward, showing how…
Contributions to credit risk
Optimisation of credit portfolios requires that risk contributions be quantified. However, there has been disagreement over which of three popular tail risk measures should be used. Here, Alexandre Kurth and Dirk Tasche offer a way forward, showing how…
Risk and probability measures
Although its drawbacks are well known, VAR has become institutionalised as the market risk measure of choice among trading firms and regulators. Now there is a growing feeling that a reappraisal is overdue, exemplified here by Phelim Boyle, Tak Kuen Siu…