机构地区: 上海对外经贸大学金融管理学院
出 处: 《投资研究》 2011年第10期123-140,共18页
摘 要: 本文以2000年至2010年的A股上市公司违法违规事件为样本,分析该类事件中信息不确定性的影响,以及市场反应中的投资者交易行为。研究发现:上市公司市场价值在事件日呈显著下跌;然而,与直觉有些相悖的是,信息不确定程度与超额累积收益呈显著正相关,这意味着在坏消息到来时,不确定性反而提高了股票的市场价值;最后,通过对各类投资者在此类事件中的净买入情况分析,我们发现不同投资者的交易行为有明显差异。机构投资者在坏消息中采用了反向交易策略,并且知情交易促进机构投资者的买入。 This paper attempts to investigate the effect of information uncertainty in market reaction and investors' trading be- haviors with the law-breaking events in Chinese stock market. Our results show that the stock price slumps in the event day. However, information uncertainty is positively related with excess return, and this finding is robust for various measures. This means when the bad news is released, information uncertainty increases stock value. Finally, we find that institutional investors and individual investors have fundamentally different trading behaviors in the event: institutional investors adopt negative feedback trading strategy while individual investors adopt positive feedback trading strategy. Information asymmetry only affects the buying of the institutional investors.
领 域: [经济管理]