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Some protein interaction data do not exhibit power law statistics

Reiko Tanaka·Tau-Mu Yi·John Doyle
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Abstract

It has been claimed that protein-protein interaction (PPI) networks are scale-free based on the observation that the node degree sequence follows a power law. Here we argue that these claims are likely to be based on erroneous statistical analysis. Typically, the supporting data are presented using frequency-degree plots. We show that such plots can be misleading, and should correctly be replaced by rank-degree plots. We provide two PPI network examples in which the frequency-degree plots appear linear on a log-log scale, but the rank-degree plots demonstrate that the node degree sequence is far from a power law. We conclude that at least these PPI networks are not scale-free.

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Reiko Tanaka, Tau-Mu Yi, John Doyle. 2005-06-27. Some protein interaction data do not exhibit power law statistics. https://doi.org/10.1016/j.febslet.2005.08.024

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