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arXiv · 0909.2005

Deterministic approximation for the cover time of trees

Uriel Feige·Ofer Zeitouni
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Abstract

We present a deterministic algorithm that given a tree T with n vertices, a starting vertex v and a slackness parameter epsilon > 0, estimates within an additive error of epsilon the cover and return time, namely, the expected time it takes a simple random walk that starts at v to visit all vertices of T and return to v. The running time of our algorithm is polynomial in n/epsilon, and hence remains polynomial in n also for epsilon = 1/n^{O(1)}. We also show how the algorithm can be extended to estimate the expected cover (without return) time on trees.

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Uriel Feige, Ofer Zeitouni. 2009-09-10. Deterministic approximation for the cover time of trees. https://arxiv.org/abs/0909.2005

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