An Analysis Of The Associated Network Based On Shareholding Relationship In Stock Market

With the development of stock markets, the investment relationships between listed companies and their shareholders are increasingly complex. Overall, because of the combined effects of various participants, the stock markets have some completely different characteristics with those have single participant. The research on the network composed of all the actors in the stock markets could capture the characteristics of the markets, which could contribute to finding out the problems exist in the markets timely and bringing inspiration for the regulators and investors of the stock markets. Therefore, it is highly necessary to conduct a study of the complex characteristics of the stock markets as a whole.Firstly, based on the review of literature, the theories associated with the stock market network and the Complex Networks are introduced. Secondly, the way to build this network is proposed:taking listed companies and their top ten shareholders as nodes, the actual investment relations between the nodes as arcs, and the amount of investment as the weights of the arcs. Thirdly, the CCER database is used to collect the research data, including the listed companies of Shanghai Stock Exchange (SSE) and Shenzhen Stock Exchange (SZSE) from 2001 to 2010, the top ten shareholders of each listed company, and the number of shares that these shareholders have. Then Pajek and Cfinder are used to analyze the network year by year and each industry in 2010. And the valuable conclusions are as follows. ⅰ) The equity-linked network of SSE and SZSE is scale-free and has small world characteristics. Most of the money is concentrated in a few listed companies who are attractive to investors. Meanwhile, most stake are concentrated in a few investors who have powerful ability to invest. Any two of listed companies or shareholders can be connected through a few investment relationships; ⅱ) The scale-free characteristics of the different industries’ networks are diverse, and the agriculture, forestry, animal husbandry and fishery have the most obvious scale-free characteristics; ⅲ) The largest investors in the SSE and SZSE are the holding companies or the parent companies of listed companies, listed companies themselves, state-owned specialized investment institutions, social security funds, and foreign investments. Foreign investments prefer extractive industry, transportation and warehousing industry, finance and insurance industry; ⅳ) A large number of communities are existed in the networks, the relationships between large amount investments are tight. More companies choose to diversify investments in the case of the global financial crisis in 2008. Relationships of investments within the financial industry are most tight and the biggest community exists in this industry. Finally, based on the above conclusions, some strategies and suggestions for stock market regulators and investors are brought out.As to the contribution, this thesis uses the real investment relationships to reflect the links of the nodes in the network instead of the correlation coefficient of stock price fluctuations or fluctuations in yield. Quantitative analysis is used to explore the characteristics of the network structure of the SSE and SZSE in general, as well as various industries. Based on these statements, some relevant implications and proposals are given. For example, "target immunity" of complex networks can be used in the regulatory process of the stock markets; the foreign investments can be used for reference of investment analysis and so on.