주가 점프 정보를 이용한 시장 효율성 비교 연구

In case of occurring a jump in stock prices which caused by a certain new information, the effect of the information will be expect to reflect on the stock price at once and in precise extent if the market is efficient. If the market is inefficient, the information that caused the stock price jump will be affecting the stock price movement after the jump. This study compares market efficiency in six major countries (Korea, Japan, China, Brazil, the United States and Germany) using stock price jump information in terms of behavioral finance. First, this study examines the presence of overreaction or underreaction phenomena using stock price jumps occurrence. The results show that the overreactions to the downward stock price jumps information exist in the Korean, Japanese, Chinese and German markets, while the overreactions to the upward stock price jumps information exist in Brazil. In addition, there exist underreactions to the upward stock price jumps information for the ascending periods of stock prices in Korea, Japan, China and the United States. Second, this study analyzes the magnitude of impact of the negative information (downward stock price jumps) and the positive information (upward stock prices jumps) on stock investors. The result of the study shows the evidences of negative effects in Korea, Japan, China and Germany, and the positive effects in Brazil and the United States. Third, this study analyzes whether or not the daily price limit system is one of the key factors affecting to the differences in market inefficiency in terms of stock price jumps information. The result shows that the implementation of the daily price limit system is a factor affecting the market inefficiency.