{ "id": "1406.1781", "version": "v2", "published": "2014-06-06T19:42:10.000Z", "updated": "2014-12-29T17:55:28.000Z", "title": "Renyi's Parking Problem Revisited", "authors": [ "Matthew P. Clay", "Nandor J. Simanyi" ], "comment": "Final version; to appear in Proceedeings of \"Probability and Dynamics at IM-UFRJ\", 13 pages, 6 figures", "categories": [ "math.PR" ], "abstract": "R\\'enyi's parking problem (or $1D$ sequential interval packing problem) dates back to 1958, when R\\'enyi studied the following random process: Consider an interval $I$ of length $x$, and sequentially and randomly pack disjoint unit intervals in $I$ until the remaining space prevents placing any new segment. The expected value of the measure of the covered part of $I$ is $M(x)$, so that the ratio $M(x)/x$ is the expected filling density of the random process. Following recent work by Gargano {\\it et al.} \\cite{GWML(2005)}, we studied the discretized version of the above process by considering the packing of the $1D$ discrete lattice interval $\\{1,2,...,n+2k-1\\}$ with disjoint blocks of $(k+1)$ integers but, as opposed to the mentioned \\cite{GWML(2005)} result, our exclusion process is symmetric, hence more natural. Furthermore, we were able to obtain useful recursion formulas for the expected number of $r$-gaps ($0\\le r\\le k$) between neighboring blocks. We also provided very fast converging series and extensive computer simulations for these expected numbers, so that the limiting filling density of the long line segment (as $n\\to \\infty$) is R\\'enyi's famous parking constant, $0.7475979203...$.", "revisions": [ { "version": "v1", "updated": "2014-06-06T19:42:10.000Z", "abstract": "R\\'enyi's parking problem (or $1D$ sequential interval packing problem) dates back to 1958, when R\\'enyi studied the following random process: Consider an interval $I$ of length $x$, and sequentially and randomly pack disjoint unit intervals in $I$ until the remaining space prevents placing any new segment. The expected value of the measure of the covered part of $I$ is $M(x)$, so that the ratio $M(x)/x$ is the expected filling density of the random process. Following recent work by Gargano {\\it et al.} \\cite{GWML(2005)}, we studied the discretized version of the above process by considering the packing of the $1D$ discrete lattice interval $\\{1,2,\\dots ,n+2k-1\\}$ with disjoint blocks of $(k+1)$ integers but, as opposed to the mentioned \\cite{GWML(2005)} result, our exclusion process is symmetric, hence more natural. Furthermore, we were able to obtain useful recursion formulas for the expected number of $r$-gaps ($0\\le r\\le k$) between neighboring blocks. We also provided very fast converging series and extensive computer simulations for these expected numbers, so that the limiting filling density of the long line segment (as $n\\to \\infty$) is R\\'enyi's famous parking constant, $0.7475979203\\dots$.", "comment": "12 pages, 6 figures", "journal": null, "doi": null }, { "version": "v2", "updated": "2014-12-29T17:55:28.000Z" } ], "analyses": { "subjects": [ "60D05" ], "keywords": [ "renyis parking problem", "random process", "randomly pack disjoint unit intervals", "sequential interval packing problem", "filling density" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1406.1781C" } } }