@Article{JCM-36-2, author = {Yang, Jie and Zhang, Guannan and Zhao, Weidong}, title = {A First-Order Numerical Scheme for Forward-Backward Stochastic Differential Equations in Bounded Domains}, journal = {Journal of Computational Mathematics}, year = {2018}, volume = {36}, number = {2}, pages = {237--258}, abstract = {
We propose a novel numerical scheme for decoupled forward-backward stochastic differential equations (FBSDEs) in bounded domains, which corresponds to a class of nonlinear parabolic partial differential equations with Dirichlet boundary conditions. The key idea is to exploit the regularity of the solution ($Y_t$, $Z_t$) with respect to $X_t$ to avoid direct approximation of the involved random exit time. Especially, in the one-dimensional case, we prove that the probability of $X_t$ exiting the domain within $∆t$ is on the order of $\mathcal{O}((∆t)^ε$exp($−1/(∆t) ^{2ε})$), if the distance between the start point $X_0$ and the boundary is at least on the order of $\mathcal{O}((∆t)^{\frac{1}{2}−ε})$ for any fixed $ε > 0$. Hence, in spatial discretization, we set the mesh size $∆x ∼ \mathcal{O}((∆t)^{\frac{1}{2}−ε})$, so that all the interior grid points are sufficiently far from the boundary, which makes the error caused by the exit time decay sub-exponentially with respect to $∆t$. The accuracy of the approximate solution near the boundary can be guaranteed by means of high-order piecewise polynomial interpolation. Our method is developed using the implicit Euler scheme and cubic polynomial interpolation, which leads to an overall first-order convergence rate with respect to $∆t$.
}, issn = {1991-7139}, doi = {https://doi.org/10.4208/jcm.1612-m2016-0582}, url = {https://global-sci.com/article/84464/a-first-order-numerical-scheme-for-forward-backward-stochastic-differential-equations-in-bounded-domains} }