{ "id": "1310.1737", "version": "v3", "published": "2013-10-07T11:43:50.000Z", "updated": "2014-09-11T08:29:26.000Z", "title": "Markov chain approximations to scale functions of Lévy processes", "authors": [ "Aleksandar Mijatović", "Matija Vidmar", "Saul Jacka" ], "comment": "45 pages, 4 figures", "categories": [ "math.PR" ], "abstract": "We introduce a general algorithm for the computation of the scale functions of a spectrally negative L\\'evy process $X$, based on a natural weak approximation of $X$ via upwards skip-free continuous-time Markov chains with stationary independent increments. The algorithm consists of evaluating a finite linear recursion with, what are nonnegative, coefficients given explicitly in terms of the L\\'evy triplet of $X$. Thus it is easy to implement and numerically stable. Our main result establishes sharp rates of convergence of this algorithm providing an explicit link between the semimartingale characteristics of $X$ and its scale functions, not unlike the one-dimensional It\\^o diffusion setting, where scale functions are expressed in terms of certain integrals of the coefficients of the governing SDE.", "revisions": [ { "version": "v2", "updated": "2013-10-21T11:45:00.000Z", "abstract": "We introduce a general algorithm for the computation of the scale functions of a spectrally negative L\\'evy process $X$, based on a natural weak approximation of $X$ via upwards skip-free continuous-time Markov chains with stationary independent increments. The algorithm consists of evaluating a finite linear recursion with coefficients given explicitly in terms of the L\\'evy triplet of $X$. It is easy to implement and fast to execute. Our main result establishes sharp rates of convergence of this algorithm providing an explicit link between the semimartingale characteristics of $X$ and its scale functions, not unlike the one-dimensional It\\^o diffusion setting, where scale functions are expressed in terms of certain integrals of the coefficients of the governing SDE.", "comment": "Reference to Matlab code for the algorithm (available online) added, Introduction revised, 43 pages, 3 figures", "journal": null, "doi": null }, { "version": "v3", "updated": "2014-09-11T08:29:26.000Z" } ], "analyses": { "subjects": [ "60G51" ], "keywords": [ "scale functions", "markov chain approximations", "lévy processes", "main result establishes sharp rates", "upwards skip-free continuous-time markov chains" ], "note": { "typesetting": "TeX", "pages": 45, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1310.1737M" } } }