Publications
Haewon Oh & Travis A. Smith. (2026). "Limiting Antidepressant Prescriptions and Suicide Risk: Evidence from South Korea." Economics & Human Biology, 61, 101603.
Soobin Kim, Isak Kim, Guijin Lee, Haewon Oh, & Orion Mowbray. (2026). "Social Determinants and the Role of School-Based Mental Health Services in Adolescents' Depressive Symptoms and Happiness." Health & Social Work, 51(2), 114–124.
Sage J. Kim, Meredith Hollender, Andrew DeMott, Haewon Oh, Ishan Bhatia, Yochai Eisenberg, Michael Gelder, & Susan Hughes. (2022). "COVID-19 Cases and Deaths in Skilled Nursing Facilities in Cook County, Illinois." Public Health Reports, 137(3), 564–572.
Sun Jeong Kim, Haewon Oh, Jong Wook Chang, & Sang Jun Kim. (2020). "Recovery of Tendon Characteristics by Inhibition of Aberrant Differentiation of Tendon-Derived Stem Cells from Degenerative Tendinopathy." International Journal of Molecular Sciences, 21(8), 2687.
Se-Jik Kim, Haewon Oh, & Syngjoo Choi. (2017). "Evaluating Information Campaigns to Reduce Food Waste: A Field Experiment." Korean Economic Journal, 56(2), 125–144. (In Korean)
Working Papers
Haewon Oh, Hugo Sant'Anna, Samyam Shrestha, & Travis Alan Smith. "The Effects of Minimum Wage Increases on SNAP Participation: Evidence from a Stacked Difference-in-Differences Design." Under review. [draft]
Do state minimum-wage increases affect SNAP participation? While earnings gains can lift family income above eligibility thresholds, lost hours and unemployment can push families onto the program. Prior studies on this question disagree on the sign and rely exclusively on state-panel two-way fixed effects (TWFE). Using minimum wage increases of at least $1 during 2000-2019, we estimate stacked event studies comparing each increase with states whose effective minimum wage remained unchanged during the same period. We show nearly half of the implicit comparisons in the TWFE design are contaminated by already-treated states, and correcting for this reverses their positive finding. Across the full population, we find no meaningful effect on either the extensive margin of participation or the intensive margin of benefit amounts. Restricting to families most likely to be near program eligibility, using a demographic screen built from pre-period data, participation rises modestly but the effect remains statistically insignificant. The response is largest in the first year after an increase, before fading, and pre-trends are flat. Reweighting households by their likelihood of treatment yields a similar pattern.
Haewon Oh, Xinyu Zeng, & Travis Alan Smith. "The Effect of the Economic Impact Payment on Consumption Behavior." Under review
This paper examines how the U.S. government’s Economic Impact Payments (EIPs) affected household spending behavior during the COVID-19 pandemic. Issued between April 2020 and March 2021 under the Coronavirus Aid, Relief, and Economic Security (CARES) Act, the EIPs aimed to provide financial relief and stimulate consumption, reaching about 160 million Americans with payments of up to $1,400 per person. Using data from the 2019 - 2023 Consumer Expenditure Survey, this study uses an event-study framework with inverse probability weighting to evaluate changes in household spending across major expenditure categories. We find modest and short-lived consumption responses. Eligible households exhibit a temporary increase in total expenditure following the first payment, but the effect dissipates thereafter. Spending increases are concentrated in flexible categories such as food away from home, alcohol, transportation, other lodging, utilities, and education, while core expenditures show little systematic response. While overall consumption responses are similar across groups, some heterogeneity appears across specific expenditure categories. Overall, the results suggest that one-time cash transfers provided short-term financial support but did not generate sustained increases in household consumption.
Work in Progress
Cognitive Skills, Education, and Earnings in New Zealand (with Thomas Schober and Lisa Meehan)
Crime Victimisation, Mental Health, and Labour Market Outcomes (with Anna Bindler, Juliane Hennecke, Nadine Ketel, Lisa Meehan, and Gail Pacheco)
The Effects of Free School Lunches on Educational Outcomes in New Zealand (with Samyam Shrestha)
Children's Healthcare Access and Long-Term Outcomes in New Zealand