Malliavin calculcus for a Hawkes process
Alexandre Popier, Laurent Denis, Dorian Cacitti-Holland
TL;DR
This work develops a local Malliavin calculus on nonlinear Hawkes processes by perturbing jump times and constructing a local Dirichlet form with a gradient and divergence. Using a Cameron–Martin-type time change, it establishes absolute continuity criteria for Hawkes-driven functionals and derives integration-by-parts formulas, enabling density results for Hawkes SDEs and Malliavin-based Greeks. The framework yields a precise, multi-layer Dirichlet structure (through directional derivatives and a full Dirichlet form via a Hilbert basis) and provides local and global density criteria under explicit conditions. Together, these results equip stochastic modeling with regularity tools for Hawkes-driven dynamics and provide practical pathways for sensitivity analysis in finance.
Abstract
We develop a Malliavin calculus for nonlinear Hawkes processes in the sense of Carlen and Pardoux. This approach, based on perturbations of the jump times of the process, enables the construction of a local Dirichlet form. As an application, we establish criteria for the absolute continuity of solutions to stochastic differential equations driven by Hawkes processes. We also derive sensitivity formulas for the valuation of financial derivatives with respect to model parameters.
