{ "id": "math/0510663", "version": "v2", "published": "2005-10-31T01:46:32.000Z", "updated": "2005-11-01T21:05:30.000Z", "title": "Avoiding defeat in a balls-in-bins process with feedback", "authors": [ "Roberto Oliveira", "Joel Spencer" ], "comment": "30 pages; to be submitted. V.2 has some minor corrections", "categories": [ "math.PR", "math.CO" ], "abstract": "Imagine that there are two bins to which balls are added sequentially, and each incoming ball joins a bin with probability proportional to the p-th power of the number of balls already there. A general result says that if p>1/2, there almost surely is some bin that will have more balls than the other at all large enough times, a property that we call eventual leadership. In this paper, we compute the asymptotics of the probability that bin 1 eventually leads when the total initial number of balls $t$ is large and bin 1 has a fraction \\alpha<1/2 of the balls; in fact, this probability is \\exp(c_p(\\alpha)t + O{t^{2/3}}) for some smooth, strictly negative function c_p. Moreover, we show that conditioned on this unlikely event, the fraction of balls in the first bin can be well-approximated by the solution to a certain ordinary differential equation.", "revisions": [ { "version": "v2", "updated": "2005-11-01T21:05:30.000Z" } ], "analyses": { "subjects": [ "60C05", "60J10", "60J20" ], "keywords": [ "balls-in-bins process", "avoiding defeat", "ordinary differential equation", "general result says", "total initial number" ], "note": { "typesetting": "TeX", "pages": 30, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2005math.....10663O" } } }