{ "id": "2207.01872", "version": "v1", "published": "2022-07-05T08:13:35.000Z", "updated": "2022-07-05T08:13:35.000Z", "title": "Optimal tail comparison under convex majorization", "authors": [ "Daniel J. Fresen" ], "comment": "9 pages. Most of the material here was originally part of arXiv:2203.12523 and/or arXiv:1812.10938 and now stands as a paper on its own", "categories": [ "math.PR" ], "abstract": "Following results of Kemperman and Pinelis, we show that if $X$ and $Y$ are real valued random variables such that $\\mathbb{E}\\left\\vert Y\\right\\vert<\\infty$ and for all non-decreasing convex $\\varphi:\\mathbb{R}\\rightarrow [0,\\infty)$, $\\mathbb{E}\\varphi(X)\\leq\\mathbb{E}\\varphi(Y)$, then for all $s\\in\\mathbb{R}$ with $\\mathbb{P}\\left\\{Y>s\\right\\}\\neq 0$, $\\mathbb{P}\\left\\{X\\geq\\mathbb{E}\\left(Y:Y>s\\right)\\right\\}\\leq\\mathbb{P}\\left\\{Y>s\\right\\}$. This bound is sharp in essentially the strictest possible sense: for any such $Y$ and $s$ there exists such an $X$ with $\\mathbb{P}\\left\\{X\\geq \\mathbb{E}\\left(Y:Y>s\\right)\\right\\}=\\mathbb{P}\\left\\{Y>s\\right\\}$.", "revisions": [ { "version": "v1", "updated": "2022-07-05T08:13:35.000Z" } ], "analyses": { "subjects": [ "60E05", "60E15" ], "keywords": [ "optimal tail comparison", "convex majorization", "real valued random variables", "non-decreasing convex" ], "note": { "typesetting": "TeX", "pages": 9, "language": "en", "license": "arXiv", "status": "editable" } } }