Mirshahvalad A, Esquivel A V, Lizana L, Rosvall M
Integrated Science Lab, Department of Physics, Umeå University, Umeå, Sweden.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Jan;89(1):012809. doi: 10.1103/PhysRevE.89.012809. Epub 2014 Jan 21.
To better understand the inner workings of information spreading, network researchers often use simple models to capture the spreading dynamics. But most models only highlight the effect of local interactions on the global spreading of a single information wave, and ignore the effects of interactions between multiple waves. Here we take into account the effect of multiple interacting waves by using an agent-based model in which the interaction between information waves is based on their novelty. We analyzed the global effects of such interactions and found that information that actually reaches nodes reaches them faster. This effect is caused by selection between information waves: lagging waves die out and only leading waves survive. As a result, and in contrast to models with noninteracting information dynamics, the access to information decays with the distance from the source. Moreover, when we analyzed the model on various synthetic and real spatial road networks, we found that the decay rate also depends on the path redundancy and the effective dimension of the system. In general, the decay of the information wave frequency as a function of distance from the source follows a power-law distribution with an exponent between -0.2 for a two-dimensional system with high path redundancy and -0.5 for a tree-like system with no path redundancy. We found that the real spatial networks provide an infrastructure for information spreading that lies in between these two extremes. Finally, to better understand the mechanics behind the scaling results, we provide analytical calculations of the scaling for a one-dimensional system.
为了更好地理解信息传播的内在机制，网络研究人员经常使用简单模型来捕捉传播动态。但大多数模型只强调局部相互作用对单个信息波全局传播的影响，而忽略了多个波之间相互作用的影响。在这里，我们通过使用基于主体的模型来考虑多个相互作用波的影响，其中信息波之间的相互作用基于它们的新颖性。我们分析了这种相互作用的全局影响，发现实际到达节点的信息会更快到达。这种效应是由信息波之间的选择导致的：滞后的波会消失，只有领先的波会存活。结果，与具有非相互作用信息动态的模型不同，信息获取随着与源的距离而衰减。此外，当我们在各种合成和真实空间道路网络上分析该模型时，我们发现衰减率还取决于路径冗余和系统的有效维度。一般来说，信息波频率随与源的距离的衰减遵循幂律分布，对于具有高路径冗余的二维系统，指数在 -0.2 之间，对于没有路径冗余的树状系统，指数在 -0.5 之间。我们发现真实空间网络为信息传播提供了一个介于这两个极端之间的基础设施。最后，为了更好地理解缩放结果背后的机制，我们提供了一维系统缩放的解析计算。
