Research on Investor Sentiment from the Perspective of a Complex Network

Considering the financial market as a complex network system, we can look at its complexity from multiple aspects. The stock market is not only a key part of the financial market, but also one of the remarkable characteristics is that the investor sentiment in China's stock market is more volatile, and the impact of this fluctuation on the stock price is also more significant. This paper takes CSI 300 as the research object, selects five indicators of price-earnings ratio, turnover rate, stock price amplitude, stock price fluctuation and liquidity, and uses the principal component analysis method to construct the investor sentiment index and prove its rationality. At the same time, based on Pearson's correlation coefficient, the stock price fluctuation network and investor sentiment network are constructed, so as to better understand the relationship between investor sentiment and stock price fluctuation, and understand investor sentiment from multiple dimensions. The empirical analysis shows the following conclusions: there is a strong correlation between investor sentiment and stock price; investor sentiment shows high consistency in the same industry; and the investor sentiment network meets the characteristics of small world network in complex network.