Neural variance reduction for stochastic differential equations
P. D. Hinds, M. V. Tretyakov
TL;DR
The work tackles high-variance Monte Carlo estimation in SDE-based pricing by introducing neural SDEs with neural-network–parameterized control variates to learn variance-reducing terms on the fly. By leveraging the Feynman–Kac link to PDEs/PIDEs, it derives optimality conditions for zero-variance control variates in Brownian and Lévy settings and develops a two-pass, online training algorithm that minimally biases the estimator. Empirical results across GBM, Heston, Merton, and higher-dimensional Lévy models show substantial speedups, up to around 40× in some cases, and competitive performance relative to MLMC and crude CV, with notable gains from transfer learning. The approach provides a flexible, black-box variance-reduction tool for pricing under complex noise structures, including infinite-activity jumps, while maintaining unbiased MC estimates and offering practical online training without extensive pretraining.
Abstract
Variance reduction techniques are of crucial importance for the efficiency of Monte Carlo simulations in finance applications. We propose the use of neural SDEs, with control variates parameterized by neural networks, in order to learn approximately optimal control variates and hence reduce variance as trajectories of the SDEs are being simulated. We consider SDEs driven by Brownian motion and, more generally, by Lévy processes including those with infinite activity. For the latter case, we prove optimality conditions for the variance reduction. Several numerical examples from option pricing are presented.
