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Growing Trees in Internet News Groups and Forums

Bernard Kujawski·Janusz A. Holyst·Geoff J. Rodgers
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Abstract

We present an empirical study of the networks created by users within internet news groups and forums and show that they organise themselves into scale-free trees. The structure of these trees depends on the topic under discussion; specialist topics have trees with a short shallow structure whereas more universal topics are discussed widely and have a deeper tree structure. For news groups we find that the distribution of the time intervals between when a message is posted and when it receives a response exhibits a composite power-law behaviour. From our statistics we can see if the news group or forum is free or is overseen by a moderator. The correlation function of activity, the number of messages posted in a given time, shows long range correlations connected with the users' daily routines. The distribution of distances between each message and its root is exponential for most news groups and power-law for the forums. For both formats we find that the relation between the supremacy (the total number of nodes that are \emph{under} the node $i$, including node $i$) and the degree is linear $s(k)\sim k$, in contrast to the analytical relation for Barabási-Albert network.

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Bernard Kujawski, Janusz A. Holyst, Geoff J. Rodgers. 2007-01-31. Growing Trees in Internet News Groups and Forums. https://doi.org/10.1103/physreve.76.036103

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