Epidemic dynamics in finite size scale-free networks
Epidemic dynamics in finite size scale-free networks
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DOI：
10.1103/physreve.65.035108
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发表时间：
2002-03-01
影响因子：
2.4
通讯作者：
Vespignani, A
中科院分区：
文献类型：
--
作者：
Pastor-Satorras, R;Vespignani, A
许多真实的网络由于物理约束或有限的网络规模而呈现出有界无标度行为和连通性截止。研究了具有软硬连通截断的有界无标度网络中的传染病动力学。由截断引入的有限尺寸效应诱导了在尺寸增加时接近于零的流行阈值。即使在一个相对较小的临界值下，诱导的流行阈值也非常小，这表明在有界无标度网络中忽略连通性波动会导致对流行阈值的严重高估。我们提供了感染率的表达式，并讨论了其有限大小的修正。本文表明，高度异质性的无标度网络不允许使用齐次近似，即使是一个相对较少的节点数量的系统。
Many real networks present a bounded scale-free behavior with a connectivity cutoff due to physical constraints or a finite network size. We study epidemic dynamics in bounded scale-free networks with soft and hard connectivity cutoffs. The finite size effects introduced by the cutoff induce an epidemic threshold that approaches zero at increasing sizes. The induced epidemic threshold is very small even at a relatively small cutoff, showing that the neglection of connectivity fluctuations in bounded scale-free networks leads to a strong overestimation of the epidemic threshold. We provide the expression for the infection prevalence and discuss its finite size corrections. The present paper shows that the highly heterogeneous nature of scale-free networks does not allow the use of homogeneous approximations even for systems of a relatively small number of nodes.