财务、会计seminar第一百一十八期讲座通知

演讲题目：1、社交媒体股市大数据被操纵了吗？--来自投资者情绪对股票收益预测的证据

2、Acquired Impulse Control? An Experimental Analysis of Cheating Among Humans Intolerant to Alcohol

演 讲 者： 王建新

中南大学商学院助理教授，厦门大学博士后

演讲时间： 2016年6月15日（周三）下午15:00—16:30

演讲地点：保欣丽英楼（嘉庚一）509

主 持 人：吴超鹏 教授

参 加 者：对会计、财务研究有兴趣的师生

讲座简介：1、近年来，大数据在社会、经济、管理等领域的科研与应用中所面临的问题迅速成为研究热点。《Nature》和《Science》分别在2008年和2011年出专刊对大数据的特征及应用前景进行讨论。随着大数据以及Web2.0技术的发展，社交媒体数据在各领域的“预测作用”和“偏差”被广泛关注。本文应用社交媒体中的投资者生成数据对股票收益进行预测从而检验社交媒体数据的偏差性。通过收集“雪球”股票论坛中的649,636条讨论数据构建投资者情绪指标进行实证研究，结果发现：（1）整体投资者情绪对股票市场收益不存在预测作用，表明社交媒体股票大数据存在显著偏差；（2）社交媒体中存在“市场操纵者”，其情绪能够引领其他用户的情绪，并存在提前买入行为；（3）“市场操纵者”的情绪与股票未来市场收益负相关，表明市场操纵者通过数据操纵达到了获利目的。这些实证结果表明：具有一定意图的投资者在社交媒体中发布具有倾向性甚至虚假的信息，从而导致整体数据产生系统性偏差。因此，大数据在生成过程中可能产生的噪声与偏差应引起研究者、监管者和投资者的注意。

2、The ability to control tempting impulses impacts health, education and general socio-economic outcomes among people at all ages. Consequently, whetherand how impulse controldevelops in adult populations is a topic of enduring interest. While past research has shed important light on this question using controlled intervention studies, here we take advantage of a natural experiment witha Han Chinese population.One-third of our sample is intolerant to alcohol, while the remaining control sample is observationally identical but alcohol tolerant. Consistent with previous literature, we find that intolerant males are significantly more likely to exercise willpower to limit their alcohol consumption than alcohol tolerant males. In view of the strength model of self-control, we hypothesize that this enables improved impulse control in other contexts as well. To investigate this, we compare decisions in laboratory games of self-control between the tolerant and intolerant groups. We find thatmales intolerant to alcohol and who frequently encounter drinking environments control their selfish impulses significantly better than their tolerant counterparts. On the other hand, and also consistent with the strength model of self-control, we find female Han Chinese intolerant to alcohol do not use self-control to limit alcohol consumption more than tolerant females, and neither do the tolerant and intolerant females exhibit differences in self-control behaviors. Our research indicates that impulse control can be developed in adult populations as a result of self-control behaviors in natural environments, and shows that this skill has generalizable benefits across behavioral domain.