• <Source Information> Xin Jing and Jin Seo Cho (2025): Working Paper.

  • <Abstract> WThis study exploits the quantile ARDL model to investigate the dynamic relationship between the confirmed COVID-19 cases and deaths in the U.S. following vaccination, with a focus on examining heterogeneity across different percentiles. The findings indicate that the confirmed case fatality rate decreased after vaccination, and the relationship between confirmed cases and deaths varies across different percentiles.