Research On Temporal Network Of Stock Price Fluctuation In China’s New Energy Vehicle Industry Chain

The new energy vehicles industry chain is a complex system composed of many different parts.The new energy vehicles industry chain stock market can reflect the intrinsic value of the listed companies in the industry chain and their position in the industry chain.This article selects the time series of the daily closing prices of 76 stocks included in Wind Database’s new energy vehicle industry chain from 2008 to 2019 as the research object,and divides the data on the monthly and quarterly time scales to form each sub-pattern,each subpattern is based on the Granger causality test result matrix,with each stock as a node.If there is a causal relationship between the prices of two stocks,there is an edge,and the Granger factor points to the Granger effect,then build a complex network of monthly or quarterly new energy vehicles industry chain stocks.On the basis of the complex network,extract the in-degree value,out-degree value,betweenness centrality,proximity centrality,clustering coefficient and other indicators of the complex network to construct monthly and quarterly time series networks corresponding to each indicator,and analyzes the evolution law of the important nodes in the network with time fluctuation.This research can not only clarify the evolution of the status of the different levels of the new energy vehicles industry chain over time,but also provide a reference for the stock market participants in the industry chain.The results show that over time,the relationship between stock price fluctuations in the new energy vehicles industry chain has become closer,the stock price of the midstream stock price leader in the new energy vehicles industry chain fluctuates,and the position of upstream stocks in the entire new energy vehicles industry chain with the gradual increase,the influence of downstream stocks gradually increases in 2019;the quarterly new energy vehicles industry chain stock price time series network can better reflect the overall trend of the industry chain;the evolution of the influence of important nodes(stocks)is volatile.For investors in new energy vehicles industry chain stocks,they should pay attention to the fluctuation of midstream stock prices when making investments.For long-term investment in new energy vehicles industry chain stocks,it is advisable to relax the research scale to more than quarterly,and when investors invest in new energy vehicles industry chain stocks,they can consider portfolio investment to reduce investment risks.