This paper considers the macroscopic and microscopic statistical features of the top 500 firms in China, the United States and the world, denoted as China 500 (CH500), Fortune 500 (US500) and Fortune Global 500 (FG500). From a macroscopic perspective, the firm size distribution of each category,...

Individual donation depends on personal wealth and individual willingness to donate. On the basis of a donation model proposed in our previous study, a simplified version of an individual donation model is derived by relaxing the restrictions of the maximum wealth in the economy. Thus, the whole...

In order to explore further the mechanism responsible for scale-free networks, we introduce two extended models of the BA model. The model A, where the system incorporates the addition of new links between existing nodes, a new node with new links and the rewiring of some links at every time...

This paper proposes a Markov chain method to predict the growth dynamics of the individual nodes in scale-free networks, and uses this to calculate numerically the degree distribution. We first find that the degree evolution of a node in the BA model is a nonhomogeneous Markov chain. An...

By analyzing the data of top 500 Chinese firms from the year 2002 to 2007, we reveal that their revenues and ranks obey the Zipf’s law with exponent of 1 for each year. This result confirms the universality of firm size character which has been presented in many other empirical works, since...

In present paper, we propose a highly clustered weighted network model that incorporates the addition of a new node with some links, new links between existing nodes and the edge's weight dynamical evolution based on weight-dependent walks at each time step. The analytical approach and numerical...

Finding out statistically significant words in DNA and protein sequences forms the basis for many genetic studies. By applying the maximal entropy principle, we give one systematic way to study the nonrandom occurrence of words in DNA or protein sequences. Through comparison with experimental...