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. -- Network of firms ; scale-free network ; complex network ; hierarchy ; degree correlation