The purpose of this paper is to summarize the development of the notion of "model risk" and present the current state of the art, before outlining open issues that must be resolved in order to define a consistent framework for measuring model risk

In this paper, motivated by the approximation of Martingale Optimal Transport problems, we are interested in sampling methods preserving the convex order for two probability measures µ and ν on ℝ^d, with ν dominating µ. When (X_i)1≤i≤I (resp. (Y_j)1≤j≤J ) are independent and...

The aim of this work is to introduce a new stochastic volatility model for equity derivatives. To overcome some of the well-known problems of the Heston model, and more generally of the affine models, we define a new specification for the dynamics of the stock and its volatility. Within this...

The no Butterfly arbitrage domain of Gatheral SVI 5-parameters formula for the volatility smile has been recently described. It requires in general a numerical minimization of 2 functions altogether with a few root finding procedures. We study here the case of some sub-SVIs (all with 3...

We work in the Uncertain Volatility Model setting of Avellaneda, Levy, Paras [1] and Lyons [10] (cf. also [11]). We first look at European options in a market with no interest rate and focus on theextreme case where the volatility has a lower bound but no upper bound. We show that the smallest...

We fully characterize the absence of Butterfly arbitrage in the SVI formula for implied total variance proposed by Gatheral in 2004. The main ingredient is an intermediary characterization of the necessary condition for no arbitrage obtained for any model by Fukasawa in 2012 that the inverse...