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arXiv · 2607.25139

Emergent contagion complexity: Disentangling mechanistic complexity from correlated heterogeneity

Katerina Tang·Daniel Kaiser·William Thompson·Jean-Gabriel Young·Laurent Hébert-Dufresne·Nicholas W. Landry
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Abstract

Simple and complex contagions differ mechanistically; multiple exposures act synergistically in the latter but independently in the former. Yet correlated mixtures of simple contagions may appear complex when inferring global contagion rules, a phenomenon we call "emergent complexity." We present a measure of contagion complexity and an inferential framework for estimating mixtures of nonparametric contagion rules from time-series data. Our work reframes past studies on complex contagion by offering heterogeneous mixtures of simple contagions as an alternative explanation.

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Katerina Tang, Daniel Kaiser, William Thompson, Jean-Gabriel Young, Laurent Hébert-Dufresne, Nicholas W. Landry. 2026-07-27. Emergent contagion complexity: Disentangling mechanistic complexity from correlated heterogeneity. https://arxiv.org/abs/2607.25139

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