Explicit numerical approximations for McKean-Vlasov stochastic differential equations in finite and infinite time
Yuanping Cui, Xiaoyue Li, Yi Liu, Fengyu Wang
TL;DR
This work tackles numerical approximation of McKean–Vlasov SDEs with superlinear coefficients by introducing an explicit truncated Euler-type scheme (TEM) that leverages propagation of chaos via an interacting particle system. It proves a strong convergence rate of order $1/2$ and shows TEM preserves long-time dynamics, including ergodicity, while ensuring convergence of the numerical invariant measure to the true one in the $L^2$-Wasserstein distance. The analysis establishes uniform-in-time propagation of chaos, non-asymptotic error bounds between numerical and true invariant measures, and exponential ergodicity for the numerical scheme. Numerical experiments in scalar and higher-dimensional settings corroborate the theory and demonstrate TEM’s robustness against particle-corruption, outperforming certain existing explicit methods in long-time simulations of MV-SDEs.
Abstract
Inspired by the stochastic particle method, this paper establishes an easily implementable explicit numerical method for McKean-Vlasov stochastic differential equations (MV-SDEs) with superlinear growth coefficients. The paper establishes the theory on the propagation of chaos in the Lq sense. The optimal uniform-in-time strong convergence rate 1/2-order of the numerical solutions is obtained for the interacting particle system. Furthermore, it is proved that the numerical solutions capture the long-term dynamical behaviors of MV-SDEs precisely, including moment boundedness, stability, and ergodicity. Moreover, a unique numerical invariant probability measure is yielded, which converges to the underlying invariant probability measure of MV-SDEs in the L2-Wasserstein distance. Finally, several numerical experiments are carried out to support the main results.
