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arXiv · 2109.01027

H\"older regularity for stochastic processes with bounded and measurable increments

Ángel Arroyo·Pablo Blanc·Mikko Parviainen
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Abstract

We obtain an asymptotic H\"older estimate for expectations of a quite general class of discrete stochastic processes. Such expectations can also be described as solutions to a dynamic programming principle or as solutions to discretized PDEs. The result, which is also generalized to functions satisfying Pucci-type inequalities for discrete extremal operators, is a counterpart to the Krylov-Safonov regularity result in PDEs. However, the discrete step size $\varepsilon$ has some crucial effects compared to the PDE setting. The proof combines analytic and probabilistic arguments.

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Ángel Arroyo, Pablo Blanc, Mikko Parviainen. 2021-09-02. H\"older regularity for stochastic processes with bounded and measurable increments. https://arxiv.org/abs/2109.01027

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