{ "id": "1712.03843", "version": "v1", "published": "2017-12-11T15:42:57.000Z", "updated": "2017-12-11T15:42:57.000Z", "title": "Breaking the Curse for Uniform Approximation in Hilbert Spaces via Monte Carlo Methods", "authors": [ "Robert J. Kunsch" ], "comment": "1 figure. Based on a chapter of the author's PhD thesis arXiv:1704.08213, yet with improved results in some settings", "categories": [ "math.NA" ], "abstract": "We study the $L_{\\infty}$-approximation of $d$-variate functions from Hilbert spaces via linear functionals as information. It is a common phenomenon in tractability studies that unweighted problems (with each dimension being equally important) suffer from the curse of dimensionality in the deterministic setting, that is, the number $n(\\varepsilon,d)$ of information needed in order to solve a problem to within a given accuracy $\\varepsilon > 0$ grows exponentially in $d$. We show that for certain approximation problems in periodic tensor product spaces, in particular Korobov spaces with smoothness $r > 1/2$, switching to the randomized setting can break the curse of dimensionality, now having polynomial tractability, namely $n(\\varepsilon,d) \\preceq \\varepsilon^{-2} \\, d \\, (1 + \\log d)$. Similar benefits of Monte Carlo methods in terms of tractability have only been known for integration problems so far.", "revisions": [ { "version": "v1", "updated": "2017-12-11T15:42:57.000Z" } ], "analyses": { "subjects": [ "41A25", "41A45", "41A63", "41A65", "65C05", "65J05" ], "keywords": [ "monte carlo methods", "hilbert spaces", "uniform approximation", "periodic tensor product spaces", "tractability studies" ], "tags": [ "dissertation" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }