A Methodology for Assessing Model Risk and its Application to the Implied Volatility Function Model

Abstract

We propose a methodology for assessing model risk and apply it to the implied volatility function (IVF) model. This is a popular model among traders for valuing exotic options. Our research is different from other tests of the IVF model in that we reflect the traders' practice of using the model for the relative pricing of exotic and plain vanilla options at one point in time. We find little evidence of model risk when the IVF model is used to price and hedge compound options. However, there is significant model risk when it is used to price and hedge some barrier options.