Strong rate of convergence of the Euler scheme for SDEs with irregular drift driven by Levy noise
arXiv:2204.12926
Abstract
We study the strong rate of convergence of the Euler--Maruyama scheme for a multidimensional stochastic differential equation (SDE) with irregular -Hölder drift, , driven by a Lévy process with exponent . For , we obtain strong and almost sure convergence rates in the entire range , where the SDE is known to be strongly well-posed. This significantly improves the current state of the art, both in terms of convergence rate and the range of . Notably, the obtained convergence rate does not depend on , which is a novelty even in the case of smooth drifts. As a corollary of the obtained moment-independent error rate, we show that the Euler--Maruyama scheme for such SDEs converges almost surely and obtain an explicit convergence rate. Additionally, as a byproduct of our results, we derive strong convergence rates for approximations of nonsmooth additive functionals of a Lévy process. Our technique is based on a new extension of stochastic sewing arguments and Lê's quantitative John-Nirenberg inequality.