RANDOM WALKS ON TREES AND AN INEQUALITY OF MEANS Introduction: Z
نویسندگان
چکیده
. We de ne trees generated by bi-in nite sequences, calculate their walkinvariant distribution and the speed of a biased random walk. We compare a simple random walk on a tree generated by a bi-in nite sequence with a simple random walk on an augmented Galton-Watson tree. We nd that comparable simple random walks require the augmented Galton-Watson tree to be larger than the corresponding tree generated by a bi-in nite sequence. This is due to an inequality for random variables with values in involving harmonic, geometric and arithmetic mean.
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