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arXiv · 1211.4314

Hypergeometric solution to a gambler's ruin problem with a nonzero halting probability

Ken Yamamoto
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Abstract

This paper treats of a kind of a gambler's ruin problem, which seeks the probability that a random walker first hits the origin at a certain time. In addition to a usual random walk which hops either rightwards or leftwards, the present paper introduces the `halt' that the walker does not hop with a certain probability. The solution to the problem can be obtained exactly using a Gauss hypergeometric function. The moment generating function of the duration is also calculated, and a calculation technique of the moments is developed. The author derives the long-time behavior of the ruin probability, which exhibits power-law behavior if the walker hops to the right and left with equal probability.

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Ken Yamamoto. 2013-01-07. Hypergeometric solution to a gambler's ruin problem with a nonzero halting probability. https://doi.org/10.1155/2013%2F831390

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