Research On The Influence Of Investor Sentiment On Stock Return Based On Network Public Opinion

With the continuous improvement of economic system and financial system towards the direction of marketization,Chinaundefineds stock market has made great progress.But compared with the foreign stock market,the distribution of investorsundefinedstructure is unreasonable,the investment knowledge is uneven,and the problems of overconfidence and disposal effect cannot be ignored.The traditional finance theory based on efficient market theory cannot explain the causes of these problems.Combining with the asset pricing theory of traditional finance,this paper explores the emergence of behavioral finance which introduces cognition,emotion and belief,and provides important ideas for the rational interpretation of stock market vision.One of the main research objects of behavioral finance theory is investor sentiment.The social media based on stock bar,blog,Weibo and social news is flooding the whole Internet space at a rapid speed.Everyone is the information publisher and recipient,and the Internet has become the main carrier of social media.Therefore,based on behavioral finance theory and BW index construction method,this paper takes January 2010-December 2018 as the research interval,selects direct index consumer confidence index,indirect index closed-end fund discount,IPO number,new investor account opening rate,stock market turnover rate,introduces network public opinion index by text mining technology,and constructs monthly investor sentiment comprehensive index by principal component analysis.Then,the market as a whole,different styles and different industries are classified,and the following conclusions are drawn: investor sentiment is a systematic factor affecting stock return,and there is a significant positive correlation between the two.The impact of investor sentiment on return is asymmetrical under different emotional states,and pessimistic shock causes greater fluctuations than optimism.When the investor mood is high,choose the small market stock,the high price earnings ratio,the high market net ratio,the high price stock,the loss stock and the industry emotion premium high investment portfolio;when the investor sentiment is low,chooses the big market stock,the low price earnings ratio,the low market net ratio,the low performance stock and the industry sentiment overflow price investment portfolio.