The Annals of Applied Probability

Asymptotic normality of the k-core in random graphs

Svante Janson and Malwina J. Luczak
Source: Ann. Appl. Probab. Volume 18, Number 3 (2008), 1085-1137.

Abstract

We study the k-core of a random (multi)graph on n vertices with a given degree sequence. In our previous paper [Random Structures Algorithms 30 (2007) 50–62] we used properties of empirical distributions of independent random variables to give a simple proof of the fact that the size of the giant k-core obeys a law of large numbers as n→∞. Here we develop the method further and show that the fluctuations around the deterministic limit converge to a Gaussian law above and near the threshold, and to a non-normal law at the threshold. Further, we determine precisely the location of the phase transition window for the emergence of a giant k-core. Hence, we deduce corresponding results for the k-core in G(n, p) and G(n, m).

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Primary Subjects: 05C80
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Links and Identifiers

Permanent link to this document: http://projecteuclid.org/euclid.aoap/1211819795
Digital Object Identifier: doi:10.1214/07-AAP478
Mathematical Reviews number (MathSciNet): MR2418239
Zentralblatt MATH identifier: 1157.05047

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The Annals of Applied Probability

The Annals of Applied Probability