Tracks to tech equity: How high-speed rail bridges the digital divide within cities? Prefecture-level evidence from China

As a cross-regional infrastructure and major public project, high-speed rail (HSR) can significantly impact regional economic development, but few studies focus on its effects on intra-regional inequality. This study takes the opening of HSR stations as a quasi-natural experiment and employs a staggered difference-in-differences (DID) model to empirically examine the characteristics and mechanisms of HSR's impact on intra-city digital inequality. The results show that: (1) The opening of HSR stations reduces digital inequality within a city, mainly because it significantly enhances the digital development level of disadvantaged counties compared to advantaged ones. (2) Mechanism analysis indicates that HSR reduces the digital divide by stimulating innovation equilibrium, financial equilibrium, and local fiscal revenue equilibrium effects within a city. (3) Heterogeneity analysis shows that HSR significantly impacts internal digital inequality only in high-slope, economically underdeveloped, and peripheral areas. (4) Spatial tests reveal that HSR also helps reduce digital inequality within neighboring cities. This study not only enriches the theoretical understanding of the economic effects of HSR development but also provides policy insights on how regions can eliminate digital inequality and close intra-regional digital divides.