How Financial Research Firms’ Reports Affect Stock Prices: Evidence from the Dow 30

• Main Authors: Ying-Hao Lee, 李英豪
• Other Authors: Jying-Nan Wang
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/2dehsy

碩士 === 佛光大學 === 應用經濟學系 === 103 === According to the Efficient-Market hypothesis (EMH), if the market is to have efficiency, the investor or professional fund managers cannot predict the future trends of a stock. However, in many financial news media, business newspapers and Business Week, we can find securities managers or analysts in the financial markets boldly predicting the future direction of a stock. This information attracts many investors who enter into investments, hoping to gain more profit. However, investors have neglected the importance of published information at a point in time, and in hindsight, it was hard to verify whether or not this news is true. The present study is to investigate that the mechanism of investment research reports can bring abnormal returns for investors, and confirm the existence of market efficiency. The studies suggested actions of directing public information through research institutions news site Yahoo Finance and collected 30 constituent stocks of the Dow Jones Industrial, to analyze the use of the event study method. The empirical results show when the event occurred, whether it was a buy or sell recommendation, the average abnormal return rate（AAR）has a phenomenal rate of return difference from zero, confirming that the proposed research institutions operating direction did attract the market's attention, resulting in abnormal fluctuations of the stock price. The cumulative average abnormal return rate（CAAR） is a show about four weeks after the incident that recommends buying the event will be quite profitable. In addition, this study discussed separately the performance of different research institutions, however, it found no significant differences between various research institutions.