The Influence of Core-Periphery Structure on Information Diffusion over Social Networks

While core-periphery (CP) structures are a fundamental property of many social networks, their influence on information diffusion remains insufficiently understood, especially for complex contagions that require social reinforcement. To address this research gap, this paper investigates the role of core-periphery (CP) structure on information diffusion using the Maki-Thompson model. Both simple contagion and complex contagion scenarios are analyzed through extensive numerical simulations and theoretical analysis. Our results reveal several key insights. First, a stronger CP structure facilitates broader information dissemination compared to a weaker core-periphery structure. Second, strong CP networks are particularly vulnerable to targeted interventions; immunizing core nodes is highly effective at impeding diffusion, especially for simple and small-k complex contagions. Third, counterintuitively, CP structure significantly hinders the spread of complex contagions, requiring a higher critical threshold for a global outbreak compared to equivalent random networks. These findings can provide valuable insights into the nuanced role of network topology in shaping information propagation, highlighting that CP structure can both facilitate and hinder diffusion depending on contagion type.