Technical paper
Risk management based on stochastic volatility
Risk management approaches that do not incorporate randomly changing volatility tend to under- or overestimate the risk, depending on current market conditions. We show how some popular stochastic volatility models in combination with the hyperbolic…
How to avoid overestimating capital charges for op risk
Pooling internal and external data is a central issue to estimating capital charges for operational risk. Here, Nicolas Baud, Antoine Frachot and Thierry Roncalli of Crédit Lyonnais discuss the methodology they have developed.
What causes crashes?
Are large market events caused by easily identifiable exogenous shocks such as major newsevents, or can they occur endogenously, without apparent external cause, as an inherent propertyof the market itself? Here, Didier Sornette, Yannick Malevergne and…
From horses to hedging
Financial derivatives rely on liquid underlying markets to work properly, but what happenswhen such underlying markets do not exist, as is the case for indexes such as GDP orunemployment? Here, Ken Baron and Jeffrey Lange suggest a parimutuel auction…
Extreme forex moves
What is the appropriate statistical description of tail risk in a market portfolio? In the context offoreign exchange, Peter Blum and Michel Dacorogna address this problem using extreme valuetheory. Using 20 years of data, they estimate parameters for an…
A decision model for selling park and loan services
The park and loan model is useful for gas storages and pipelines. The concept can be applied to many ‘when to sell’-type decisions. Here, Huagang ‘Hugh’ Li considers selling park and loan services as a financial and statistical decision on revenue and…
Testing rating accuracy
As Basel II approaches the implementation stage, regulators have identified internal ratings validation as a key challenge for banks using this approach. Here, Bernd Engelmann, Evelyn Hayden and Dirk Tasche build upon previous research showing how to use…
Op risk modelling for extremes
Part 2: Statistical methods In this second of two articles, Rodney Coleman, of Imperial College London, continues his demonstration of the uncertainty in measuring operational risk from small samples of loss data.
Why be backward?
Originally developed as a tool for calibrating smile models, so-called forward methods can also be used to price options and derive Greeks. Here, Peter Carr and Ali Hirsa apply the technique to the pricing of continuously exercisable American-style put…
Coarse-grained CDOs
While analytical models of credit portfolio risk using conditional independence have been one of the most promising areas of recent research, they often involve granularity assumptions that are violated in CDO reference portfolios. Here, Michael Pykhtin…
Dealing with discrete dividends
Over the past year, we have published several papers on the issue of options on stocks with discrete dividends. At least three distinct models are used by practitioners, involving trade-offs between accuracy and tractability. Here, Remco Bos, Alexander…
The front-month proxy hedge
The front-month proxy hedge is a correlation-based hedge that seeks to neutralise the aggregate sensitivity of a portfolio to a futures curve by converting the individual futures hedges into a single hedge with respect to only the front-month contract…
Volatile volatilities
When pricing exotic interest rate derivatives, calibration of model parameters to vanilla cap or swaption prices can be especially time-consuming, especially if stochastic volatility is incorporated into the standard Libor market models or low…
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…
Weather option pricing with transaction costs
The weather derivatives market is becoming more liquid, and dynamic hedging of weather options with weather swaps is now possible, though limited by transaction costs. Here Stephen Jewson investigates the effect of such hedging on option pricing
Unsystematic credit risk
Although Basel has shifted its treatment of unsystematic credit risk from the first, capital rules pillar (where it was called the 'granularity adjustment') to the second, supervisory pillar of the forthcoming Accord, this issue is of great practical…
Unsystematic credit risk
Although Basel has shifted its treatment of unsystematic credit risk from the first, capital rules pillar (where it was called the ‘granularity adjustment’) to the second, supervisory pillar of the forthcoming Accord, this issue is of great practical…