Research On The Market Effect Of The Change Of Securities Short Names Of Listed Companyies In China

In recent years,the phenomenon of the abbreviation of listed companies in China has become more and more fierce.Some of these companies' abbreviations have changed because of changes in control or industrial upgrading.Such stock renaming is normal.However,there are still many companies whose stock abbreviation changes do not have substantive reasons,but merely to move closer to the hot industry.Why are so many listed companies needing to change their stock short names? How much of this is a non-substantial initiative to change its name? How does the change in securities abbreviation affect the market?This paper takes the Shanghai and Shenzhen A-share listed companies between January 1,2017 and September 30,2018 as a sample,and uses the market adjustment model to calculate the excess return rate of stocks and the cumulative excess return rate,based on different reasons for change and securities.The vocabulary contained in the abbreviation is tested for significance and variance according to multiple angles.The research results show that when a listed company changes its securities abbreviation,the speculative behavior generally occurs when the proposed change announcement is issued,and there is no strong reaction in the market when the official change notice is issued.There is a significant positive excess return rate during the announcement of the securities abbreviation,and the market will carry out certain reverse corrections.The change of the securities abbreviation may be referred to as the initial change of the listed company's securities abbreviation.The change is divided into substantive active renaming and non-substantial active renaming,substantial active renaming and no substantive proactive renaming.There is a significant difference in the market response during the announcement period,in which non-substantial active renaming has overreaction indicating that China's stock market violated half.Strong and effective assumptions;companies with vocabulary of “technical”,“ke” and “smart” in the stock short name after the change,whether there is a substantial change in the stock abbreviation before or after the change,or there is no substantial change in the market Speculation,further illustrating the existence of serious concepts and subject speculation in China's stock market.