{ "id": "2404.06598", "version": "v1", "published": "2024-04-09T20:00:13.000Z", "updated": "2024-04-09T20:00:13.000Z", "title": "Extremes of generalized inversions on symmetric groups", "authors": [ "Philip Dörr" ], "categories": [ "math.CO" ], "abstract": "The classical inversion statistic on symmetric groups is the sum of all indicators $\\textbf{1}\\{\\pi(i) > \\pi(j)\\}$ for a random permutation $\\pi = (\\pi(1), \\ldots, \\pi(n))$ and the pairs $(i,j)$ with $1 \\leq i < j \\leq n$. The descent statistic counts all $i \\in \\{1, \\ldots, n-1\\}$ with $\\pi(i) > \\pi(i+1)$. The number of inversions can be generalized by restricting the indicators to pairs $(i,j)$ with $i \\pi(i+d)$. These generalized statistics can be further extended to the signed and even-signed permutation groups. The bandwidth index $d$ can be chosen in dependence of $n$, and the magnitude of $d$ is significant for asymptotic considerations. It is known that each of these statistics is asymptotically normal for suitable choices of $d$. In this paper we prove the bivariate asymptotic normality and determine the extreme value asymptotics of generalized inversions and descents.", "revisions": [ { "version": "v1", "updated": "2024-04-09T20:00:13.000Z" } ], "analyses": { "subjects": [ "60G70", "05A16", "20F55" ], "keywords": [ "symmetric groups", "generalized inversions", "descent statistic counts", "bivariate asymptotic normality", "extreme value asymptotics" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }