Research
Research
1. Overtime Hours Reform and Labor Market Outcomes: Evidence from South Korea (Job Market Paper), Current Version: Link, Presented in SEA 2025 and CREED 2025
Abstract: South Korea implemented an overtime hours reform in 2018. Utilizing legal work hours reform based on industry and firm size at different phases, we find that the overtime hours reform reduces the number of overtime hours and overtime earnings. However, the overtime hours reform increases standard hours worked, thereby resulting in a null effect on total hours worked. We find that the overtime hours reform increases the likelihood of being full-time employment and monthly earnings among women. We further discuss gender heterogeneity and groups that were not affected by the policy. Overall, the reform may redistribute working hours among workers, potentially influencing women's employment outcomes.
2. Labor Supply and Savings Responses to Increasing the Pension Eligibility Age in South Korea (with Jonathan M. Leganza and Devon Gorry), under review, Current Version: Link
Abstract: We study how people responded to a reform in South Korea that increased the full pension eligibility age. Using regression discontinuity, we document the causal effects of the reform on several potential margins of adjustment. Consistent with studies in other settings, we find clear evidence of delayed benefit claiming. However, in contrast with other studies, we find little-to-no statistical evidence of changes in labor supply. We also find no evidence of changes in savings or spending. The South Korean pension is relatively new, and benefit replacement rates are comparatively modest, which may have contributed to muted responses.
3. The Impact of Legalized Recreational Marijuana Laws on Obesity (with Reginald B. Hebert and Eye Eoun (Ian) Jung), Current version: being revised, Presented in ASHecon 2025: Poster
Abstract: This study investigates the causal effect of recreational marijuana laws (RMLs) on body mass index (BMI) using data from the CDC’s Behavioral Risk Factor Surveillance System (BRFSS) from 1990 to 2024. While numerous studies have explored the association between marijuana use and appetite, few have examined the causal evidence between marijuana use and BMI. Leveraging the staggered adoption of RMLs as a natural experiment, we employ a Two-Stage Difference-in-Difference (2SDiD) and Synthetic DiD model to estimate the effect of RMLs on BMI. Although our initial 2SDiD point estimates indicate a significant decrease in BMI of approximately 0.294 units or 1.08 percent (0.294/27.33), the event-study analysis reveals a downward pre-trend in BMI prior to the implementation of RMLs. After accounting for the Goodman-Bacon adjustment procedure, our findings suggest that RMLs have no statistically significant effect on BMI. Moreover, we find little evidence for potential mechanisms or heterogeneous effects depending on gender and age groups.
4. The Effect of Involuntary Job Loss on Subjective Well-Being and Health Behaviors (with Sunwoo Park and Reginald B. Hebert), under review, Current Version: link
Abstract: Despite extensive research on the association between economic conditions and health outcomes, there is limited and inconclusive evidence regarding the effects of job displacement on subjective well-being and health behaviors. Using longitudinal job history and survey data on involuntary job loss due to plant closures and layoffs, we identify the causal effect of job loss on individuals' overall well-being, perceived economic and socioeconomic outcomes, and health behaviors in South Korea. We find that job loss is associated with a decrease in overall subjective well-being, which then increases as job search activity decreases. However, we do not find evidence that job loss is associated with overall health behaviors.
The Effects of Standard Hours Regulation on Labor Supply and On-the-Job Training
Legalized Recreational Marijuana Laws and Health Demand Market (with Sarah Anastasia Webb)
The Effect of Retirement on Health Behaviors and Overall Life Satisfaction: Evidence from South Korea (with Devon Gorry and Jonathan M. Leganza)
Park, H., An, J., & Kim, D. (2025). Gender-Specific Effects of Smoking Cessation on Drinking: Evidence from a Randomized Trial. Journal of Drug Issues, doi.org/10.1177/00220426251384854. [SSCI]
Kim, D., Park, H., & An, J. (2024). The Effect of Smoking Cessation Caused by Cigarette Price Increase on Drinking Behaviors. American Journal of Health Behavior, 48(3), 725-733. [SSCI]
Park, H., & An, J. (2024). The Analysis of Mortality Rates by Income Levels and its Implications for Income Redistribution under the National Pension Scheme. Journal of Pension Studies, 14(1), 59-75. (In Korean) - Granted by the Korea Pension Association
An, J., & Park, H. (2024). The Effect of Public Pension Benefit on Individuals' Economics Satisfaction and Expectation. Journal of Pension Studies, 14(1), 121-140. (In Korean) - Granted by the Korea Pension Association
Kim, D., An, J., & Seong, M. (2020). A Behavioral Analysis of Private Pension Consumers: Do Individuals Supplement Public Pensions with Private Pensions? Korea Institute for Health and Social Affairs, 40(2), 556-580. (In Korean)
Kim, D., Lee, D., & An, J. (2019). Contributions of the National Pension Scheme to Retirement Stability: Expectations and Reality. The Journal of Risk Management, 30(3), 87-115. (In Korean)