Smartphone Trading Technology, Investor Behavior, and Mutual Fund Performance
利用一家大型投资顾问推出智能手机交易应用的自然实验数据，研究了智能手机交易技术如何影响散户投资者行为和共同基金业绩，发现应用采用者增加交易和关注，导致基金异常回报下降。
Using proprietary individual-level trading data around a natural experiment—the release of a smartphone trading app by a large investment advisor—this study investigates how smartphone trading technology affects retail investor behavior and mutual fund performance. App adoption by retail investors leads to an increase in investor attention and trading volume. App adopters’ flows become more sensitive to short-term fund returns and market sentiment, resulting in higher aggregate flow volume among adopters. The funds more exposed to the shock experience a greater decline in abnormal returns, likely attributable to higher fund flow volume and liquidity costs. As a result, both adopters and nonadopters experience a decline in their mutual fund investment returns. This paper was accepted by Lin William Cong, finance. Funding: The W. Edwards Deming Center and the Eugene Lang Entrepreneurship Center at Columbia University provided funding to support this research. Supplemental Material: The online appendices and data files are available at https://doi.org/10.1287/mnsc.2021.02099 .