{ "id": "math/0406392", "version": "v3", "published": "2004-06-20T11:33:40.000Z", "updated": "2006-03-10T16:31:23.000Z", "title": "Level Crossing Probabilities I: One-dimensional Random Walks and Symmetrization", "authors": [ "Rainer Siegmund-Schultze", "Heinrich von Weizsaecker" ], "comment": "10 pages, some references added, typos corrected", "categories": [ "math.PR" ], "abstract": "We prove for an arbitrary one-dimensional random walk with independent increments that the probability of crossing a level at a given time n has the order of square root of n. Moment or symmetry assumptions are not necessary. In removing symmetry the (sharp) inequality P(|X+Y| <= 1) < 2 P(|X-Y| <= 1) for independent identically distributed X,Y is used. In part II we shall discuss the connection of this result to 'polygonal recurrence' of higher-dimensional walks and some conjectures on directionally random walks in the sense of Mauldin, Monticino and v.Weizsaecker [5].", "revisions": [ { "version": "v3", "updated": "2006-03-10T16:31:23.000Z" } ], "analyses": { "subjects": [ "60G51" ], "keywords": [ "level crossing probabilities", "probability", "arbitrary one-dimensional random walk", "symmetrization", "independent increments" ], "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math......6392S" } } }