Gaussian model

A dynamic model for correlation

Equity markets have experienced a significant increase in correlation during the crisis, resulting in exotic derivatives portfolios realising large losses. As larger correlations in downward scenarios are already implied in the index option market in the…

Individual names in top-down CDO pricing models

The Gaussian copula collapsed as a means of pricing collateralised debt obligations in the crisis of 2008, as to match prices and deltas nonsensical correlation parameters were required. By adapting the traditional framework to cater for more general…

Putting the smile back on the face of derivatives

Cross-asset quadratic Gaussian models have been limited in the scale of their implementation by the difficulty in ensuring the correct drift conditions to omit arbitrage. Here, Paul McCloud shows how to exploit the symmetries of the functional form to…

Unbiased risk-neutral loss distributions

Luigi Vacca introduces entropy maximisation (ME) to derive portfolio loss probabilities that are consistent with standard tranche prices on a credit default swap index. Tranche prices that are calculated using ME are free of arbitrage. A numerical…