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arXiv · 1805.00360

Optimal community structure for social contagions

Zhen Su·Wei Wang·Lixiang Li·H. Eugene Stanley·Lidia A. Braunstein
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Abstract

Community structure is an important factor in the behavior of real-world networks because it strongly affects the stability and thus the phase transition order of the spreading dynamics. We here propose a reversible social contagion model of community networks that includes the factor of social reinforcement. In our model an individual adopts a social contagion when the number of received units of information exceeds its adoption threshold. We use mean-field approximation to describe our proposed model, and the results agree with numerical simulations. The numerical simulations and theoretical analyses both indicate that there is a first-order phase transition in the spreading dynamics, and that a hysteresis loop emerges in the system when there is a variety of initially-adopted seeds. We find an optimal community structure that maximizes spreading dynamics. We also find a rich phase diagram with a triple point that separates the no-diffusion phase from the two diffusion phases.

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Zhen Su, Wei Wang, Lixiang Li, H. Eugene Stanley, Lidia A. Braunstein. 2018-05-01. Optimal community structure for social contagions. https://doi.org/10.1088/1367-2630%2Faac0c9

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