The Scale-free Topology of Investment Relationship in China Stock Market

Using the complex network methods, we have constructed bipartite networks of investment relationship between CSl 300 constituent stocks and their top 10 investment fund shareholders with data released on December 31, 2010. Here we analyze a variety of structure properties of these networks, including the average distance, clustering coefficient, and overlapping community structure. Studying the structure of this graph is essential for understanding the structural properties of the investment relationship it represents. The scale-free and small world properties of the funds network and the stock network are found, which gives a way to explain the investment policy adopted by institutional investors. The community structure of the fund network shows that few fund investors have great influence and certain investment funds in the same community have convergence in investment philosophy.