The Impact Of Media News Sentiment On Stock Prices

The " Spiral of Silence " theory holds that the opinions emphasized and recommended by the mass media can easily be regarded as "majority opinions" or "dominant opinions" due to their openness and universality;The pressure or sense of security generated by this environmental perception will lead to a spiral upward process of "unwelcome opinions silence" and "stronger opinions" in the expression of opinions.The limited attention theory believes that investors' attention is limited.When investors are faced with huge amounts of information at the same time,their processing capabilities are limited.Certain events in the financial market will attract and re-allocate investors' attention,thereby affecting investors' investment behavior and investment decisions.Based on the " Spiral of Silence " and "limited attention" theory,this article studies the impact of changes in media sentiment on the stock market from the perspective of behavioral finance.First,obtain the text data of media reports from the CSMAR news database.Secondly,pre-process the data,and use a combination of text analysis and manual reading to ensure the accuracy of the media sentiment index.Next,calculate the average daily media news sentiment to measure the comprehensive tendency of media sentiment conveyed in daily news reports.At the same time,the daily average media positive sentiment index and negative sentiment index are sorted separately to explore the influence of different types of media sentiment tendencies on the stock price.Then,the stability test of the Shanghai and Shenzhen 300 Index in the same period is carried out,the stock index logarithmic return rate is calculated,and the GARCH model is constructed to analyze the influence of media news sentiment on the stock index return rate and stock index volatility.The conclusion is that the media news sentiment index has a significant positive impact on the yield of the CSI300 stock index,that is,the more positive the sentiment conveyed by the media reports,the more the yield of the CSI 300 index has a rising trend,and vice versa.The more negative the sentiment conveyed by the media reports,the more the Shanghai and Shenzhen 300 stock index yields have a downward trend.However,the media news sentiment index has no significant impact on the volatility of the Shanghai and Shenzhen stock indexes,and the volatility is greatly affected by the volatility of the previous period.In terms of categories,whether it is positive media news sentiment or negative media news sentiment,both have a significant impact on the Shanghai and Shenzhen stock index yields,and there is an asymmetric effect.Negative sentiments have a much higher impact on the stock index yields.Positive emotions.Finally,the article summarizes and analyzes the research results and shortcomings of this article,and based on this,puts forward some policy recommendations and expectations for future research.