Strong uniform Wong--Zakai approximations of Lévy-driven Marcus SDEs
Ilya Pavlyukevich, Sooppawat Thipyarat
TL;DR
This paper analyzes strong Wong–Zakai type approximations for Lévy-driven Marcus SDEs, establishing both a global strong convergence rate of $1/2$ and a locally uniform rate of $(1-\varepsilon)/(4d)$ for the non-linear polygonal approximation scheme. The authors construct a Wong–Zakai scheme $X^h$ using polygonal approximations of the Brownian motion and a pure-jump Lévy process, and they lever the Marcus flow $\boldsymbol{\varphi}^z$ and the non-autonomous map $\boldsymbol{\ Ψ}$ to derive sharp error bounds. Under a comprehensive set of smoothness and integrability assumptions, they prove existence, uniqueness, and moment bounds for the Marcus SDE, then prove strong convergence of the scheme with explicit rates both globally (in initial data $x$) and locally (uniform on bounded sets in $x$). The locally uniform result is obtained via Kunita’s random-field framework, revealing how the convergence rate degrades with dimension as $h^{(1-\varepsilon)/(4d)}$; these results provide rigorous, dimension-aware guarantees for simulating Lévy-driven Marcus SDEs. This advances the numerical analysis of jump-diffusions and supports reliable simulations in applications requiring strong pathwise accuracy.
Abstract
For a solution $X$ of a Lévy-driven $d$-dimensional Marcus (canonical) stochastic differential equation, we show that the Wong--Zakai type approximation scheme $X^h$ has a strong convergence of order $\frac12$: for each $T\in [0,\infty)$ and all $x\in\mathbb R^d$ we have $$ \mathbf E \sup_{kh\leq T}|X_{kh}(x)-X^h_{kh}(x)|\leq C h^{\frac{1}{2}}(1+|x|),\quad h\to 0. $$ We also determine the rate of the locally uniform strong convergence: for each $N\in(0,\infty)$ and $\varepsilon\in (0,1)$ we have $$ \mathbf E\sup_{|x|\leq N}\sup_{kh\leq T}|X_{kh}(x)-X^h_{kh}(x)|\leq C h^{\frac{1-\varepsilon}{4d}},\quad h\to 0. $$
