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arXiv · 2010.03647

Actor-Critic Algorithm for High-dimensional Partial Differential Equations

Xiaohan Zhang
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Abstract

We develop a deep learning model to effectively solve high-dimensional nonlinear parabolic partial differential equations (PDE). We follow Feynman-Kac formula to reformulate PDE into the equivalent stochastic control problem governed by a Backward Stochastic Differential Equation (BSDE) system. The Markovian property of the BSDE is utilized in designing our neural network architecture, which is inspired by the Actor-Critic algorithm usually applied for deep Reinforcement Learning. Compared to the State-of-the-Art model, we make several improvements including 1) largely reduced trainable parameters, 2) faster convergence rate and 3) fewer hyperparameters to tune. We demonstrate those improvements by solving a few well-known classes of PDEs such as Hamilton-Jacobian-Bellman equation, Allen-Cahn equation and Black-Scholes equation with dimensions on the order of 100.

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BibTeXRIS

Xiaohan Zhang. 2020-10-07. Actor-Critic Algorithm for High-dimensional Partial Differential Equations. https://arxiv.org/abs/2010.03647

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