Network Structure of Japanese Firms. Scale-Free, Hierarchy, and Degree Correlation : Analysis from 800,000 Firms

We analyze fundamental characteristics of the inter-firm transaction network through the data of 800,000 Japanese firms. We find that there exists a hierarchical structure and a negative degree correlation in this transaction network. We also find that this undirected network is a scale-free network. We bring to light these characteristics of the network and discuss why there is an important need to conduct research work on the actual network structure. --