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Nonparametric Bayesian Inference for Stochastic Reaction-Diffusion Equations

Statistics Theory 2025-07-10 v1 Probability Statistics Theory

Abstract

We consider the Bayesian nonparametric estimation of a nonlinear reaction function in a reaction-diffusion stochastic partial differential equation (SPDE). The likelihood is well-defined and tractable by the infinite-dimensional Girsanov theorem, and the posterior distribution is analysed in the growing domain asymptotic. Based on a Gaussian wavelet prior, the contraction of the posterior distribution around the truth at the minimax optimal rate is proved. The analysis of the posterior distribution is complemented by a semiparametric Bernstein--von Mises theorem. The proofs rely on the sub-Gaussian concentration of spatio-temporal averages of transformations of the SPDE, which is derived by combining the Clark-Ocone formula with bounds for the derivatives of the (marginal) densities of the SPDE.

Keywords

Cite

@article{arxiv.2507.06857,
  title  = {Nonparametric Bayesian Inference for Stochastic Reaction-Diffusion Equations},
  author = {Randolf Altmeyer and Sascha Gaudlitz},
  journal= {arXiv preprint arXiv:2507.06857},
  year   = {2025}
}
R2 v1 2026-07-01T03:53:12.568Z