论文标题
分形结构的合作组织
Organization of cooperation in fractal structures
论文作者
论文摘要
众所周知，小世界结构构成了足够的条件来维持合作并增强合作。相反，通常认为平均距离很长的网络被认为是抑制合作的出现。在本文中，我们表明，平均距离很长的分形结构并不总是在合作组织中起负面作用。与常规网络相比，分形结构甚至可能有助于合作的出现。这主要取决于局部紧凑的簇的存在。这些集群之间的稀疏间互连构成了一个不对称的障碍，即叛逃策略几乎不可能穿越，但是合作策略的机会并不小。更一般而言，只要存在此类结构，网络就不必成为标准分形。反过来，当缺乏这种典型的结构时，分形结构还将抑制合作的出现，例如通过稀释随机树状网络获得的分形构型。我们的发现还阐明了以前的研究中的一些矛盾，并表明从/插入/插入常规网络的链接都可以增强合作。
It is known that the small-world structure constitutes sufficient conditions to sustain cooperation and thus enhances cooperation. On the contrary, the network with a very long average distance is usually thought of as suppressing the emergence of the cooperation. In this paper we show that the fractal structure, of which the average distance is very long, does not always play a negative role in the organization of cooperation. Compared to regular networks, the fractal structure might even facilitate the emergence of cooperation. This mainly depends on the existence of locally compact clusters. The sparse inter-connection between these clusters constructs an asymmetric barrier that the defection strategy is almost impossible to cross, but the cooperation strategy has a not too small chance. More generally, the network need not to be a standard fractal, as long as such structures exist. In turn, when this typical structure is absent, the fractal structure will also suppress the emergence of the cooperation, such as the fractal configuration obtained by diluting a random tree-like network. Our findings also clarify some contradictions in the previous studies, and suggest that both removing and inserting links from/into a regular network can enhance cooperation.
