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arXiv · math/0702884

Integration by parts formula for locally smooth laws and applications to sensitivity computations

Abstract

We consider random variables of the form $F=f(V_1,...,V_n)$, where $f$ is a smooth function and $V_i,i\in\mathbb{N}$, are random variables with absolutely continuous law $p_i(y) dy$. We assume that $p_i$, $i=1,...,n$, are piecewise differentiable and we develop a differential calculus of Malliavin type based on $\partial\ln p_i$. This allows us to establish an integration by parts formula $E(\partial_iϕ(F)G)=E(ϕ(F)H_i(F,G))$, where $H_i(F,G)$ is a random variable constructed using the differential operators acting on $F$ and $G.$ We use this formula in order to give numerical algorithms for sensitivity computations in a model driven by a Lévy process.

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BibTeXRIS

Vlad Bally, Marie-Pierre Bavouzet, Marouen Messaoud. 2007-02-28. Integration by parts formula for locally smooth laws and applications to sensitivity computations. https://doi.org/10.1214/105051606000000592

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