Analysis Of The Linkage Relationship Of The Industry Sector In The A-share Market

With the rapid development of China's capital market,the A-share market has grown to become the second largest stock market in the world.The continued financial security and stable investment returns have increasingly attracted the attention of the Chinese government and various investors.Research is also getting deeper.Whether there is linkage between the stock market industries,and whether this linkage can be used to increase investor returns,reduce investment risks,and provide policy basis for regulatory agencies has become a question worthy of further investigation.Aiming at the above problems,based on Tongdaxin's primary industry stock index as the basic data,based on the non-linear Granger causality,we constructed the A-share market industry sector yield linkage network and volatility linkage network,using social network analysis methods,respectively The rate linkage network and the volatility linkage network analyze the overall network structural characteristics,centrality,and block models,and conduct in-depth research on the nature of the network and industry associations.The results show that: in the yield linkage network,the various sectors of the Chinese stock market exhibit a stable nonlinear linkage network structure with reciprocity;the five sectors of petroleum,power supply and heating,insurance,securities and power are at the center "Position,with the largest number of associations with other industry sectors;chemical fiber,gas and heat supply,electricity,transportation equipment,water services and other industries are" net overflow"subgroups,with obvious spillover effects,and the winemaking sector is in the revenue network.The edge group and the subgroup of "isolators" have relative independence in the revenue network.In the volatility linkage network,the non-linear linkage relationship network structure is relatively stable and infectious;steel,daily chemical industry,business agents,electrical equipment,telecommunications operations and insurance and other industry sectors are important "bridges" that cause cross-influence of stock market risks.The household goods,IT equipment,food and beverage industries are at the "edge" position of the volatility network,indicating that high consumption and high-tech industries with high industry barriers have better stability and are less affected by overall market fluctuations.Finally,this article gives relevant investment suggestions and policy recommendations: various investors should have a deep understanding of the relationship between industries,and use the logic of the industry chain and the direction of information spillover between industries to improve investment returns and reduce investment risks;government agencies should increase Supervise the relevant news of the "core" industry and the "net overflow" subgroup.When major positive and negative news appears,it will promptly provide investors with risk warnings,and at the sametime prevent false news from disrupting the market and promote the steady development of the entire stock market.