Poncela Julia, Gómez-Gardeñes Jesús, Floría Luis M, Sánchez Angel, Moreno Yamir
Institute for Biocomputation and Physics of Complex Systems (BIFI), Universidad of Zaragoza, Zaragoza, Spain.
PLoS One. 2008 Jun 18;3(6):e2449. doi: 10.1371/journal.pone.0002449.
In spite of its relevance to the origin of complex networks, the interplay between form and function and its role during network formation remains largely unexplored. While recent studies introduce dynamics by considering rewiring processes of a pre-existent network, we study network growth and formation by proposing an evolutionary preferential attachment model, its main feature being that the capacity of a node to attract new links depends on a dynamical variable governed in turn by the node interactions. As a specific example, we focus on the problem of the emergence of cooperation by analyzing the formation of a social network with interactions given by the Prisoner's Dilemma. The resulting networks show many features of real systems, such as scale-free degree distributions, cooperative behavior and hierarchical clustering. Interestingly, results such as the cooperators being located mostly on nodes of intermediate degree are very different from the observations of cooperative behavior on static networks. The evolutionary preferential attachment mechanism points to an evolutionary origin of scale-free networks and may help understand similar feedback problems in the dynamics of complex networks by appropriately choosing the game describing the interaction of nodes.
尽管其与复杂网络的起源相关，但形式与功能之间的相互作用及其在网络形成过程中的作用在很大程度上仍未得到探索。虽然最近的研究通过考虑现有网络的重新布线过程引入了动态性，但我们通过提出一种进化优先连接模型来研究网络的增长和形成，其主要特征是节点吸引新链接的能力取决于一个反过来由节点相互作用控制的动态变量。作为一个具体例子，我们通过分析由囚徒困境给出相互作用的社会网络的形成来关注合作出现的问题。所得到的网络展现出许多真实系统的特征，比如无标度度分布、合作行为和层次聚类。有趣的是，诸如合作者大多位于中间度节点上的结果与在静态网络上对合作行为的观察非常不同。进化优先连接机制指出了无标度网络的进化起源，并且通过适当地选择描述节点相互作用的博弈，可能有助于理解复杂网络动力学中的类似反馈问题。
