A spectral-compensated scheme for space-parameter Poisson noise functionals: error bounds and complexity estimates
arXiv:2607.27657
The paper proposes a spectral‑compensated discretisation scheme for Poisson noise functionals, showing that replacing small discarded amplitudes with matched Gaussian noise improves the Wasserstein‑1 error to linear order and reduces computational complexity, with theoretical error bounds and numerical verification.
Abstract
This paper computes Poisson space noise functionals, , realised in a Gel'fand triple built from a Lévy measure . We isolate three discretisation parameters: a small-amplitude cut-off, a Donsker delta truncation M, and a chaos order N. For a stable-type intensity (), replacing discarded small amplitudes with matched Gaussian space noise improves the Wasserstein-1 error from to . The residual is asymptotically normal at . This compensation reduces computational complexity from to . We also evaluate the Gamma-type boundary () and exponential tempering. Truncations converge algebraically (M) and super-geometrically (N). All predicted rates are tightly confirmed by deterministic numerical experiments via Gil-Pelaez inversion, eliminating Monte Carlo noise.
24 pages, 7 figures. Submitted for publication