{ "id": "1111.4159", "version": "v3", "published": "2011-11-17T17:22:59.000Z", "updated": "2013-01-10T16:33:46.000Z", "title": "Power and exponential moments of the number of visits and related quantities for perturbed random walks", "authors": [ "Gerold Alsmeyer", "Alexander Iksanov", "Matthias Meiners" ], "comment": "38 pages", "categories": [ "math.PR" ], "abstract": "Let $(\\xi_1,\\eta_1),(\\xi_2,\\eta_2),...$ be a sequence of i.i.d.\\ copies of a random vector $(\\xi,\\eta)$ taking values in $\\R^2$, and let $S_n := \\xi_1+...+\\xi_n$. The sequence $(S_{n-1} + \\eta_n)_{n \\geq 1}$ is then called perturbed random walk. We study random quantities defined in terms of the perturbed random walk: $\\tau(x)$, the first time the perturbed random walk exits the interval $(-\\infty,x]$, $N(x)$, the number of visits to the interval $(-\\infty,x]$, and $\\rho(x)$, the last time the perturbed random walk visits the interval $(-\\infty,x]$. We provide criteria for the a.s.\\ finiteness and for the finiteness of exponential moments of these quantities. Further, we provide criteria for the finiteness of power moments of $N(x)$ and $\\rho(x)$.", "revisions": [ { "version": "v3", "updated": "2013-01-10T16:33:46.000Z" } ], "analyses": { "subjects": [ "60G50", "60G40" ], "keywords": [ "exponential moments", "related quantities", "perturbed random walk visits", "perturbed random walk exits", "finiteness" ], "note": { "typesetting": "TeX", "pages": 38, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1111.4159A" } } }