Hung-Hao Chang

Department of Agricultural Economics
National Taiwan University
No 1, Roosevelt Rd, Sec 4
Taipei 10617

Institutional Affiliation: National Taiwan University

NBER Working Papers and Publications

July 2020COVID-19 Prevention and Air Pollution in the Absence of a Lockdown
with Chad Meyerhoefer, Feng-An Yang: w27604
Recent studies demonstrate that air quality improved during the coronavirus pandemic due to the imposition of social lockdowns. We investigate the impact of COVID-19 on air pollution in the two largest cities in Taiwan, which were not subject to economic or mobility restrictions. Using a generalized difference-in-differences approach and real-time data on air quality and transportation, we estimate that levels of sulfur dioxide, nitrogen dioxide and particulate matter increased 5 - 12 percent relative to 2017 - 2019. We demonstrate that this counterintuitive finding is likely due to a shift in preferences for mode of transport away from public transportation and towards personal automobiles. Similar COVID-19 prevention behaviors in regions or countries emerging from lockdowns could likewis...
June 2020COVID-19 and the Demand for Online Food Shopping Services: Empirical Evidence from Taiwan
with Chad Meyerhoefer: w27427
We investigate how the coronavirus pandemic affected the demand for online food shopping services using data from the largest agri-food e-commerce platform in Taiwan. We find that an additional confirmed case of COVID-19 increased sales by 5.7% and the number of customers by 4.9%. The demand for grains, fresh fruit and vegetables, and frozen foods increased the most, which benefited small farms over agribusinesses. Online food shopping was highly responsive to COVID-19 media coverage and online content. Because Taiwan did not impose a stay-at-home order, the demand for online food shopping may be similar in other countries after they lift mobility restrictions.
January 2020Do Elections Make You Sick?
with Chad Meyerhoefer: w26697
Anecdotal reports and small-scale studies suggest that elections are stressful, and might lead to a deterioration in voters’ mental well-being. Nonetheless, researchers have yet to establish whether elections actually make people sick, and if so, why. By applying a regression discontinuity design to administrative health care claims from Taiwan, we determine that elections increased health care use and expense only during legally specified campaign periods by as much as 19%. Overall, the treatment cost of illness caused by elections exceeded publicly reported levels of campaign expenditure, and accounted for 2% of total national health care costs during the campaign period.
May 2018Inter-brand Competition in the Convenience Store Industry, Store Accessibility and Healthcare Utilization
with Chad D. Meyerhoefer: w24628
We investigate the impact of access to convenience stores and competition between convenience store chains on medical care use and expenditures in Taiwan; the country with the highest density of convenience stores in the world. Our study makes use of insurance claims from 0.85 million individuals enrolled in Taiwan’s national health insurance program from 2002-2012 and administrative data on convenience store chain sales. While we find that both greater store accessibility and higher levels of inter-brand competition reduce the use and cost of outpatient medical services and prescription drugs, healthcare utilization is more responsive to changes in competition. Since convenience stores in Taiwan are typically the healthier option for ready-to-eat food, we postulate that the decline in med...

Published: Chang, Hung-Hao & Meyerhoefer, Chad D., 2019. "Inter-brand competition in the convenience store industry, store density and healthcare utilization," Journal of Health Economics, Elsevier, vol. 65(C), pages 117-132. citation courtesy of

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