{ "id": "2410.22038", "version": "v1", "published": "2024-10-29T13:45:11.000Z", "updated": "2024-10-29T13:45:11.000Z", "title": "A Cramér-Wold theorem for mixtures", "authors": [ "Ricardo Fraiman", "Leonardo Moreno", "Thomas Ransford" ], "comment": "11 pages", "categories": [ "math.PR" ], "abstract": "We show how a Cram\\'er-Wold theorem for a family of multivariate probability distributions can be used to generate a similar theorem for mixtures (convex combinations) of distributions drawn from the same family. Using this abstract result, we establish a Cram\\'er-Wold theorem for mixtures of multivariate Gaussian distributions. According to this theorem, two such mixtures can be distinguished by projecting them onto a certain predetermined finite set of lines, the number of lines depending only on the total number Gaussian distributions involved and on the ambient dimension. A similar result is also obtained for mixtures of multivariate $t$-distributions.", "revisions": [ { "version": "v1", "updated": "2024-10-29T13:45:11.000Z" } ], "analyses": { "subjects": [ "60B11" ], "keywords": [ "cramér-wold theorem", "total number gaussian distributions", "cramer-wold theorem", "multivariate probability distributions", "multivariate gaussian distributions" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable" } } }