{ "id": "1105.0062", "version": "v2", "published": "2011-04-30T08:42:45.000Z", "updated": "2012-02-07T21:30:10.000Z", "title": "A Wiener-Hopf Type Factorization for the Exponential Functional of Levy Processes", "authors": [ "Pierre Patie", "Juan Carlos Pardo Milan", "Mladen Savov" ], "doi": "10.1112/jlms/jds028", "categories": [ "math.PR" ], "abstract": "For a L\\'evy process $\\xi=(\\xi_t)_{t\\geq0}$ drifting to $-\\infty$, we define the so-called exponential functional as follows \\[{\\rm{I}}_{\\xi}=\\int_0^{\\infty}e^{\\xi_t} dt.\\] Under mild conditions on $\\xi$, we show that the following factorization of exponential functionals \\[{\\rm{I}}_{\\xi}\\stackrel{d}={\\rm{I}}_{H^-} \\times {\\rm{I}}_{Y}\\] holds, where, $\\times $ stands for the product of independent random variables, $H^-$ is the descending ladder height process of $\\xi$ and $Y$ is a spectrally positive L\\'evy process with a negative mean constructed from its ascending ladder height process. As a by-product, we generate an integral or power series representation for the law of ${\\rm{I}}_{\\xi}$ for a large class of L\\'evy processes with two-sided jumps and also derive some new distributional properties. The proof of our main result relies on a fine Markovian study of a class of generalized Ornstein-Uhlenbeck processes which is of independent interest on its own. We use and refine an alternative approach of studying the stationary measure of a Markov process which avoids some technicalities and difficulties that appear in the classical method of employing the generator of the dual Markov process.", "revisions": [ { "version": "v2", "updated": "2012-02-07T21:30:10.000Z" } ], "analyses": { "subjects": [ "60G51", "60J25", "47A68", "60E07" ], "keywords": [ "exponential functional", "wiener-hopf type factorization", "levy processes", "ascending ladder height process", "fine markovian study" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1105.0062P" } } }