Document Type



Doctor of Philosophy (PhD)


Business Administration

First Advisor's Name

Jonathan Milian

First Advisor's Committee Title

Committee chair

Second Advisor's Name

Abhijit Barua

Second Advisor's Committee Title

Committee member

Third Advisor's Name

Clark Wheatley

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

Qiang Kang

Fourth Advisor's Committee Title

Committee member


Earnings announcement, individual investor, retail investor, Robinhood, COVID-19 pandemic

Date of Defense



The recent remarkable rise in the number of individual (retail) investors using new electronic trading applications increases the growing demand for research on individual investors’ trading activities. This dissertation consists of two essays focused on the trading activities of individual investors on the Robinhood (electronic trading) apps. The first essay examines individual investors’ trading activities related to scheduled accounting disclosures (i.e., earnings announcements). Findings suggest that individual investors trade significantly both before and after earnings announcements (EA), but this pattern becomes weaker during the COVID-19 pandemic. In addition, I find a significant increase in trading during the after-hours on an earnings announcement (EA) day relative to non-EA day, and that this effect decreases during the COVID-19 pandemic. Furthermore, I find that individual investors show buying behavior after both good news and bad news, indicating attention induced trading, rather than contrarian. During the pandemic, this trend is largely maintained, but the effect becomes weaker.

The second essay examines individual investors’ trading patterns. First, I examine individual investors’ preferred trading times during the day, and find that there is a strong trend for individual investors trading and buying at higher levels in the morning. Second, I examine whether individual investors trade after the market closes, and I find that individual investors are active in after-hours trading. This after-hours trading increases during the COVID-19 pandemic. Third, I examine which day of the week individual investors prefer to trade, and I find that Mondays are the highest day for trading before and during the COVID-19 pandemic, and this trend became more pronounced during the COVID-19 pandemic.

Overall, this dissertation provides additional insights into individual investors’ attention-induced, and contrarian trading activity, using a more direct proxy for (first-time, young, small) individual investors and a more granular analysis at the hourly level than prior studies. Furthermore, this dissertation provides timely evidence of the effects of the COVID-19 pandemic on individual investors.



Included in

Accounting Commons



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