Education
Ph.D. in Finance (in progress) Merage School of Business, UC Irvine
M.S. in Business Administration - Finance Seoul National University
Bachelor of Business Administration Bachelor of Art in Psychology Ewha Womans University
Research Interest
My name is Hee-Seo, pronounced HEE‑suh. I am currently a rising sixth-year PhD student, deeply interested in exploring behavioral finance, particularly in investor decision-making.
I will be on the job market during the 2026-27 academic year.
My research focuses on understanding how individual behaviors, cognitive biases, and market dynamics interact to shape financial world.
Through this website, I aim to share my academic journey and research updates. Whether you're a fellow researcher or simply curious about behavioral finance, I hope you’ll find something here that resonates with you.
Thank you for visiting, and I look forward to sharing more with you soon!
with David Hirshleifer, Jinfei Sheng, and Zheng Sun
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We hypothesize that later sunsets and clock changes disrupt sleep, impairing investor’s information processing and trading performance. Using geographic and seasonal sunset differences and daylight saving time transitions, we find that later sunset predicts lower abnormal returns on retail trades. Later sunset is also associated with weaker trading responses to earnings announcements and stronger tilts against earnings surprises. Later sunset is more negatively associated with performance for announcement-stock trades than for other trades. Together, these findings indicate that environmental factors influence the information processing and trading outcomes of investors.
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with Xindi He and Daniel Weagley
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We conduct the first large-scale analysis of the retail investor trading tendencies documented in the finance literature. We examine each tendency's excess prevalence relative to random trading and how tendencies relate to stock-selection performance using Finnish registry, U.S. brokerage, and TAQ data. We find close to 75% of the previously documented tendencies are present in all three settings. Trades associated with more tendencies earn lower future returns on average. The underperformance costs are mainly concentrated in tendencies to purchase stocks with transient features (e.g., extreme winners), especially in high-retail-clientele stocks. These transient tendencies account for 9%-26% of average retail underperformance. We find similar trading patterns after the release of ChatGPT, and that LLM recommendations exhibit similar tendencies when prompted to help a trader earn ambitious return goals (e.g., a 90% 12-month return). Overall, the results suggest trading tendencies are ubiquitous, costly, and are likely to continue if retail investors use LLMs to seek outsized gains from stock selection.
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Solo-authored
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Does emphasis on an investment theme sustain demand for thematic exchange-traded funds (ETFs)? Using 8,201 fund-report observations for 506 passive U.S. thematic and sector ETFs from 2011 to 2025, I find an association between story share and subsequent primary-market flows. Story share measures emphasis on the investment theme relative to investment results. A one-standard-deviation increase in story share is associated with a 3.03-percentage-point larger six-month cumulative redemption response for thematic ETFs than for sector ETFs, a difference equivalent to approximately 15% of average six-month gross redemptions among thematic funds. This difference persists in within-filing and covariate-balanced comparisons, remains after controlling for tone, and is not confined to poor performance. Positive creation responses appear among non-technology thematic funds, particularly social themes. These contrasting responses are consistent with differences in how investors interpret continued emphasis on an investment theme after product launch.
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:linkedin: Linkedin Page
:vm9nxqac_400x400: Author Page
Work in Progress
Languages
● English (fluent)
● Korean (native)
Awards
Financial News & KAFA Doctoral Student Dissertation Award Korea America Finance Association | 2026
MFIN Outstanding Teaching Assistant UC Irvine | 2023, 2024, 2025, 2026
Ray Watson Doctoral Fellowship UC Irvine | 2024
High Pass on Comprehensive exam UC Irvine | 2023
DUO-Korea Fellowship ASEM-DUO | 2015
Beta Gamma Sigma, Business Honors Society Ewha Womans University | 2014-