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Abstract :
[en] Since 2008 and its financial crisis, an increasing attention has been devoted to the selection of an adequate error distribution in risk models, in
particular for Value-at-Risk (VaR) predictions. We propose a robust methodology to select the most appropriate error distribution candidate, in a
classical multiplicative heteroscedastic model. In a first step, unlike to the traditional approach, we do not use any GARCH-type estimation of the
conditional variance. Instead, we propose to use a recently developed nonparametric procedure: the Local Adaptive Volatility Estimation (LAVE).
The motivation for using this method is to avoid a possible model misspecification for the conditional variance. In a second step, we suggest
a set of estimation and model selection procedures tests based on the so-obtained residuals. These methods enable to assess the global fit of a
given distribution as well as to focus on its behaviour in the tails. Finally, we illustrate our methodology on three time series (UBS stock returns,
BOVESPA returns and EUR/USD exchange rates).