Research

Published Papers

• Flexible Demand Estimation with Nonparametric Income Effect: An Application to Pass-Through and Merger Analysis. 2025 (with Yuta Toyama) The Journal of Industrial Economics 73 (1), 186-233 [Journal Link]
• Does traditional price policy work for achieving low smoking rate? – Empirical and theoretical evaluation based on the United States aggregate data. 2020 (with Haruko Noguchi) Applied Economics, 52(18), 1986-1997. [Journal Link] (Based on my undergraduate senior thesis)
• Differences in cancer patients’ work-cessation risk, based on gender and type of job: Examination of middle-aged and older adults in super-aged Japan. 2020 (with Haruko Noguchi, Rong Fu, Cheolmin Kang, Akira Kawamura, Shinsuke Amano, and Atsushi Miyawaki) PloS one, 15(1), e0227792. [Journal Link]
• How do cardiovascular diseases harm labor force participation? Evidence of nationally representative survey data from Japan, a super-aged society. 2019 (with Rongu Fu, Haruko Noguchi, Cheolmin Kang, Akira Kawamura, Hideto Takahashi,Nanako Tamiya) PloS one, 14(7), e0219149. [Journal Link]

Working Papers

• Heating Price and Infant Health [SSRN] (Under Review)　
  [Abstract]
  This paper shows how the price of home heating can affect adverse birth outcomes when mothers are exposed to cold temperatures. To this end, I leverage geographical variation in the type of energy used for home heating, temporal variation in natural gas prices triggered by the fracking boom, and variation in exposure to cold temperatures. Using the universe of births in the US for 2001-2015, I find robust evidence that higher home-heating prices increase the risk of very preterm birth when pregnant women are exposed to cold temperatures. As a possible mechanism for this result, I examine the role of the "heat-and-eat" trade-off. When heating prices rise, households may use less heating. However, if the price elasticity of heating demand is less than one, energy spending will increase, reducing the budget for other goods. Consistent with this hypothesis, I find that an increase in energy expenses leads to a reduction in food expenditures. The heterogeneity analyses reveal that the detrimental effect of higher heating prices is stronger in poorer counties and among non-Hispanic black, less-educated, and younger mothers. Back-of-the-envelope calculations imply the substantial reduction in natural gas prices in the late 2000s prevented approximately 2,200 very preterm births per year.

Work in Progress

• The Effects of Low-Level Fluoride Exposure on Dental Health and Skill Formation (with Cheolmin Kang)　[Draft coming soon]　
  [Abstract]
  Although water fluoridation is widely recognized as a highly effective public health intervention, the appropriate dosage of fluoride remains a subject of ongoing debate. This study estimates the causal effects of childhood fluoride exposure at levels lower than those typically used in artificial fluoridation programs, leveraging quasi-exogenous variation in naturally occurring fluoride concentrations driven by regional geology in Japan. By combining this variation with unique longitudinal data tracking individuals from birth and nationally representative medical claims and patient survey data, we examine impacts on dental health and human capital development. We find that at low concentrations, fluoride significantly improves a range of dental health outcomes, despite widespread access to alternative preventive measures such as fluoride toothpaste. We find no evidence of adverse effects on educational attainment, unlike concerns raised by studies of higher exposures. Importantly, fluoride exposure enhances non-cognitive skills, including self-esteem, GRIT, openness, and conscientiousness among females, but not males. The results suggest improved self-confidence in own appearance as the key mechanism. Overall, our findings suggest that dental health plays an important role in shaping non-cognitive development, particularly for girls, and point to the existence of a “bliss point” in fluoride dosage that yields health and non-cognitive developmental benefits without cognitive harm.
• Disentangling Sources of Variation in Cesarean Delivery Rates (with Stefanie Fischer, Heather Royer, and Corey White) [Draft coming soon]
• Place-Based Determinant of Birth Weight - Evidence from Moving Couples
• Gender-Neutral Curriculum and Fertility - Evidence from Curriculum Reform Using Exact Date of Birth