Research On The Impact Of The "national Team" Entry Operation On The Volatility Of The A-share Market

After the stock market crash of June 2015,with Securities company as the representative of the "national team" funds to support large-scale market.At first,the position of the "national team" to buy and sell stocks on the market is the "leveling fund",that is,the government set up institutions in a legal way and reverse operation in the stock market to reduce irrational market fluctuations and stabilize the market.The national team entering the market has played a positive role in alleviating the market sentiment,but after the crash,the national team still holds a large number of stocks,and the company has frequent storehouse behavior,causing the ordinary investors to blindly follow the wind.Therefore,the research on the effectiveness,efficiency and objective impact of the "national team" capital market entry operation has important theoretical and practical value.Based on the abnormal fluctuation of "6.15" A shares in 2015,this paper first compares and analyzes the shareholding characteristics of the "national team" before and after entering the market.Then,with the Shanghai stock index of June 2015 ~2015 in November as the research subject,the influence of the "national team" capital into the volatility of the A stock market is studied by using the autoregressive heteroscedasticity model.And taking 1767 listed companies of A shares as the research subject,based on the data of the listed companies in the three quarter of 2013 in the three quarter of ~2017,the impact of the short line operation of the "national team" on the volatility of the A share market is analyzed by the multiple linear regression method.The results show that the "national team" entered the stock market on a large scale in the three quarter of 2015,with a higher stock market value in the two or three quarter of2017 and the finance industry with the highest proportion of shareholding."National team" capital into the market can reduce the volatility of the A share market,and the short line operation of the "national team" such as Securities company,Huijin company and other "national teams" has increased the volatility of the A share market,which has interfered with the operation of the market to some extent.On the basis of the above conclusions,some countermeasures and suggestions such as the timely withdrawal of the national team fund,the operation of the rescue fund,the strengthening of the supervision and the establishment of the information disclosure system are put forward to promote the sustainable and healthy development of the capital market.