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arXiv · 1011.1788

Bayesian anomaly detection methods for social networks

Nicholas A. Heard·David J. Weston·Kiriaki Platanioti·David J. Hand
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Abstract

Learning the network structure of a large graph is computationally demanding, and dynamically monitoring the network over time for any changes in structure threatens to be more challenging still. This paper presents a two-stage method for anomaly detection in dynamic graphs: the first stage uses simple, conjugate Bayesian models for discrete time counting processes to track the pairwise links of all nodes in the graph to assess normality of behavior; the second stage applies standard network inference tools on a greatly reduced subset of potentially anomalous nodes. The utility of the method is demonstrated on simulated and real data sets.

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Nicholas A. Heard, David J. Weston, Kiriaki Platanioti, David J. Hand. 2010-11-08. Bayesian anomaly detection methods for social networks. https://doi.org/10.1214/10-aoas329

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