A New Topological Parameter of Scale-Free Network
无标度网络的一个新的拓扑参数

To characterize scale-free network topology more intuitively and profoundly,Lorenz curve and Gini coefficient which describe income inequality in economics are generalized into complex networks where people in economics are corresponding to nodes in networks and income is corresponding to node degree.Through some fundamental simulations and mathematical analysis,it is found that by these two concepts one can characterize the heterogeneity of complex networks and can compare the heterogeneity of different complex networks,e.g.it is found that Internet is more heterogeneous than the star-shaped network of the same nodes.By evaluating Gini coefficients and dipicting Lorenz curves of 15 scale-free networks with their degree distribution exponents between 1 and 4,the reason why degree distribution exponents of most of real networks are located between 2 and 3 is explained.