Why high-speed rail causes heterogeneous spatial patterns in firm innovation: Perspectives from intensive and extensive margins

This paper decompose the impact of high-speed rail (HSR) on firm innovation into extensive (more firms innovating) and intensive (firms innovating more) margins, revealing that the net positive effect is a trade-off between beneficial knowledge spillovers and a detrimental “brain drain” from peripheral counties to urban centers. While HSR boosts overall innovation, it can exacerbate regional inequality, necessitating targeted policies to support innovation in peripheral areas and mitigate the brain drain effect.