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arXiv · 2112.13079

Aligning random graphs with a sub-tree similarity message-passing algorithm

Giovanni Piccioli·Guilhem Semerjian·Gabriele Sicuro·Lenka Zdeborová
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Abstract

The problem of aligning Erdös-Rényi random graphs is a noisy, average-case version of the graph isomorphism problem, in which a pair of correlated random graphs is observed through a random permutation of their vertices. We study a polynomial time message-passing algorithm devised to solve the inference problem of partially recovering the hidden permutation, in the sparse regime with constant average degrees. We perform extensive numerical simulations to determine the range of parameters in which this algorithm achieves partial recovery. We also introduce a generalized ensemble of correlated random graphs with prescribed degree distributions, and extend the algorithm to this case.

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Giovanni Piccioli, Guilhem Semerjian, Gabriele Sicuro, Lenka Zdeborová. 2022-05-04. Aligning random graphs with a sub-tree similarity message-passing algorithm. https://doi.org/10.1088/1742-5468%2Fac70d2

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