Karrer Brian, Newman M E J
Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA.
Phys Rev Lett. 2009 Mar 27;102(12):128701. doi: 10.1103/PhysRevLett.102.128701. Epub 2009 Mar 23.
Directed acyclic graphs make up a fundamental class of networks that includes citation networks, food webs, and family trees, among others. Here we define a random graph model for directed acyclic graphs and give solutions for a number of the model's properties, including connection probabilities and component sizes, as well as a fast algorithm for simulating the model on a computer. We compare the predictions of the model to a real-world network of citations between physics papers and find surprisingly good agreement, suggesting that the structure of the real network may be quite well described by the random graph.
有向无环图构成了一类基本的网络,其中包括引用网络、食物网和家族树等。在这里,我们定义了一种有向无环图的随机图模型,并给出了该模型的一些属性的解决方案,包括连接概率和组件大小,以及一种在计算机上模拟该模型的快速算法。我们将该模型的预测与物理论文之间的真实引用网络进行比较,发现惊人的良好一致性,这表明随机图可能很好地描述了真实网络的结构。