A Numerical scheme to approximate the solution of the planar Skorokhod embedding problem
Mrabet Becher, Maher Boudabra, Fathi Haggui
TL;DR
This paper addresses approximating the μ-domain in the planar Skorokhod embedding problem (PSEP) by studying stability of the Gross domain under weak convergence $μ_n ightarrow μ$ with bounded support. A key methodological core is expressing the construction in terms of the quantile function $q$ and its approximants $q_n$, and proving that $q_n o q$ in $L^1$ implies the corresponding univalent maps $G_n(z) = abla ext{(coefficients)}$ converge to $G(z)$ uniformly on compact subsets of the unit disk, yielding convergence of the μ-domains. The paper introduces alpha_p-convergence as a general framework, offers truncation-based schemes for unbounded support, and derives convergence rates (typically $O(1/n)$) with explicit error terms depending on the cdf and its density. Numerical simulations across several distributions demonstrate robustness and practical viability, and the approach is compatible with established constructions such as Boudabra–Markowsky.
Abstract
We present a numerical framework to approximate the $μ$-domain in the planar Skorokhod embedding problem (PSEP), recently appeared in \cite{gross2019}. Our approach investigates the continuity and convergence properties of the solutions with respect to the underlying distribution $μ$. We establish that, under weak convergence of a sequence of probability measures $(μ_n)$ with bounded support, the corresponding sequence of $μ_n$-domains converges to the domain associated with $μ$, limit of $(μ_n)$. We derive explicit convergence results in the $L^1$ norm, supported by a generalization using the concept of $α_p$-convergence. Furthermore, we provide practical implementation techniques, convergence rate estimates, and numerical simulations using various distributions. The method proves robust and adaptable, offering a concrete computational pathway for approximating $μ$-domains in the PSEP.
