A Sharp Tail Bound for the Expander Random Sampler
نویسندگان
چکیده
Consider an expander graph in which a μ fraction of the vertices are marked. A random walk starts at a uniform vertex and at each step continues to a random neighbor. Gillman showed in 1998 that the number of marked vertices seen in a random walk of length n is concentrated around its expectation, Φ := μn, independent of the size of the graph. Here we provide a new and sharp tail bound, improving on the existing bounds whenever μ is not too large.
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عنوان ژورنال:
- CoRR
دوره abs/1703.10205 شماره
صفحات -
تاریخ انتشار 2017