Expected shortfall
JP Morgan's 'London whale' losses spark VAR debate
In-house probe will look at role of internal model change, among other factors
Basel Committee proposes scrapping VAR
Review recommends switch to expected shortfall, postpones CVA charge overhaul, and retains split between banking and trading books
Quants weigh up VAR's flawed alternatives
VAR at risk
Beyond Basel 2.5: regulators prepare trading book review
Beyond Basel 2.5
Goodbye VAR? Basel to consider other risk metrics
Trading book review will look at replacing value-at-risk, but quants say the obvious alternative - expected shortfall - is not much better
Delayed Basel trading book review will be broad, say supervisors
Basel Committee is expected to consider wide range of topics, including VAR, liquidity, CVA and the line between banking and trading books - but overall capital requirements are not likely to change
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…
In-house System of the Year - Point, Lehman Brothers
Risk Awards 2008
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
VAR versus expected shortfall
John Hull discusses the limitations of VAR and the relative advantages of an alternative measure, expected shortfall
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…
Basel's CDO solution
As the Basel Committee on Banking Supervision continues its stately progress towards a revised capital Accord, one area remains under debate: the proposed capital rules for asset securitisations.
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…