The Impact Of Social Media On The Stock Price Crash Risk

In recent years,the speed of China's economic development has been at a relatively high level,but the number of stock market surges and crashes has also been higher than the global average.The stock price crash has seriously disrupted the market order and poses a great hidden danger to the securities market,so research on stock price crash risk is becoming more and more popular.The amount of information that investors possess affects their investment decisions,and thus becomes a major factor affecting the risk of stock price crashes.Social media platforms represented by Weibo have greatly shortened the distance between people and played an increasingly critical role in information dissemination.These platforms not only facilitate people's lives,but also broaden the information channels for investors.Therefore,there is a certain connection between the stock price crash risk and the information disclosed on social platforms such as Weibo.Based on information asymmetry theory,principal-agent theory,signaling theory,and stock price crash risk theory,this study uses data from 2016Q1 to2020Q2 of Shanghai A-share listed companies to examines the impact of Weibo disclosure on the companies' future stock price crash risk.This study also studies the mediating role of multiple agency costs in its influence mechanism.The research results mainly show that:(1)Weibo disclosure can reduce the stock price crash risk by reducing the degree of information asymmetry.The Agency Cost I between management and shareholders plays a part of the intermediary role,but the Agency Cost II between large and small shareholders does not play a role in the process of Weibo disclosure influencing the stock price crash risk;(2)The information disclosed on Weibo has the characteristics of "non-significant",and its weight in investors' decision-making declines during special periods;(3)Noise Weibo will dilute the impact of disclosure of Weibo;(4)Compared with large-cap stocks,the stock price crash risk of non-large-cap stocks is more affected by Weibo disclosures.Based on these conclusions,this study puts forward several policy recommendations for the government and market supervision departments to further regulate market information disclosure.