Economists and financial analysts have begun to recognise the importance of the actions of other agents in the decision-making process. Herding is the deliberate mimicking of the decisions of other agents. Examples of mimicry range from the choice of restaurant, fash-ion and financial market...

I show how the problems with zero and negative values in decomposition can in principle be resolved by avoiding ill-defined mathematical operations used to derive the decomposition formulae (division by zero and taking logarithms of zero and negative values). Referring to integral approximation,...

The papers in this special issue of Mathematics and Computers in Simulation cover the following topics. Improving judgmental adjustment of model-based forecasts, whether forecast updates are progressive, on a constrained mixture vector autoregressive model, whether all estimators are born equal....

In [4], the authors introduced a Markov copula model of portfolio credit risk. This model solves the top-down versus bottom-up puzzle in achieving efficient joint calibration to single-name CDS and to multi-name CDO tranches data. In [4], we studied a general model, that allows for stochastic...

We value CDS spreads and kth-to-default swap spreads in a tractable shot noise model. The default dependence is modelled by letting the individual jumps of the default intensity be driven by a common latent factor. The arrival of the jumps is driven by a Poisson process. By using conditional...

We investigate optimal buy-and-hold strategies for terminal wealth problems in a multi-period framework. As terminal wealth is a sum of dependent random variables, each of these variables corresponding to an amount of capital that has been invested in a particular asset at a particular date, we...

We value synthetic CDO tranche spreads, index CDS spreads, kth-to-default swap spreads and tranchelets in an intensity-based credit risk model with default contagion. The default dependence is modelled by letting individual intensities jump when other defaults occur. The model is reinterpreted...

We model dynamic credit portfolio dependence by using default contagion in an intensity-based framework. Two different portfolios (with 10 obligors), one in the European auto sector, the other in the European financial sector, are calibrated against their market CDS spreads and the corresponding...

I show how the problems with zero and negative values in decomposition can in principle be resolved by avoiding ill-defined mathematical operations used to derive the decomposition formulae (division by zero and taking logarithms of zero and negative values). Referring to integral approximation,...

We study a model for default contagion in intensity-based credit risk and its consequences for pricing portfolio credit derivatives. The model is specified through default intensities which are assumed to be constant between defaults, but which can jump at the times of defaults. The model is...