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arXiv · 1704.06339

A Monte Carlo approach to computing stiffness matrices arising in polynomial chaos approximations

Juan Galvis·O. Andres Cuervo
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Abstract

We use a Monte Carlo method to assemble finite element matrices for polynomial Chaos approximations of elliptic equations with random coefficients. In this approach, all required expectations are approximated by a Monte Carlo method. The resulting methodology requires dealing with sparse block-diagonal matrices instead of block-full matrices. This leads to the solution of a coupled system of elliptic equations where the coupling is given by a Kronecker product matrix involving polynomial evaluation matrices. This generalizes the Classical Monte Carlo approximation and Collocation method for approximating functionals of solutions of these equations.

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Juan Galvis, O. Andres Cuervo. 2017-04-20. A Monte Carlo approach to computing stiffness matrices arising in polynomial chaos approximations. https://arxiv.org/abs/1704.06339

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