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arXiv · 1611.05475

The Bayesian Formulation and Well-Posedness of Fractional Elliptic Inverse Problems

Nicolas Garcia Trillos·Daniel Sanz-Alonso
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Abstract

We study the inverse problem of recovering the order and the diffusion coefficient of an elliptic fractional partial differential equation from a finite number of noisy observations of the solution. We work in a Bayesian framework and show conditions under which the posterior distribution is given by a change of measure from the prior. Moreover, we show well-posedness of the inverse problem, in the sense that small perturbations of the observed solution lead to small Hellinger perturbations of the associated posterior measures. We thus provide a mathematical foundation to the Bayesian learning of the order ---and other inputs--- of fractional models.

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Nicolas Garcia Trillos, Daniel Sanz-Alonso. 2016-11-16. The Bayesian Formulation and Well-Posedness of Fractional Elliptic Inverse Problems. https://doi.org/10.1088/1361-6420%2Faa711e

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