Abnormal Phenomena from the Largest Block Trading

• Main Authors: Tsai-Jia Wen, 蔡佳雯
• Other Authors: Chun-Nan Chen
• Format: Others
• Language: en_US
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/13146624719097418603

碩士 === 國立成功大學 === 財務金融研究所 === 91 === Abstract Recently, as the security market grows, block trading becomes a frequent phenomenon and has great impact on the market. Although many researchers were interested in the study of block trading, their studies focused on block trading from institutional investors and examined how block trading affects stock prices and returns. Different from theirs, my study pays attention to an impact of the largest block trade from an individual stock which bears the characteristics of an outlier. By using event study methodology, this study examines whether there is abnormal phenomena as soon the largest block trade occurs. Here, abnormal phenomena include abnormal returns, abnormal volatility and abnormal liquidity. There appears to be little understanding in the impact of the largest block trade and this study is expected fill the void. The findings are as follows. There are significant abnormal phenomena at least on the event day. Although there is usually no abnormal return, volatility, and liquidity prior to and posterior to the event day, the cumulative abnormal phenomena, however, do exist prior or posterior to the event period and even during the entire event window. Abnormal return implies that the market is not efficient enough to make price reflect a security’s true value right away. On the other hand, one can make profits by buying the options immediately after a super-block trade. Moreover, trading posterior to the block trade is better than trading prior to the block trade because of abnormal liquidity. All the above provide evidence that a largest block trade will affect the behavior of investors and the market structure. Except the cumulative abnormal phenomena, test results are robust to different periods.