High-speed rail operation network and urban economic development in western China: A spatial difference-in-differences approach

The implementation of large-scale, interconnected High-Speed Rail (HSR) projects is shifting westwards in China, raising significant concerns among governments and planners about their impact on the economic development of less developed inland cities. This study, which is based on data from western inland China from 2009 to 2021, constructs an HSR operation network (HSRON) to analyse the impact of city nodes' HSR network importance (HSRI) on urban economic development via a network analysis and continuous spatial difference-in-differences (SDID) model. The research findings indicate that (1) the HSRON in the western area has a multicentric structure with provincial capitals serving as mediator nodes; (2) the HSRON has considerable positive and spatial spillover effects on urban economies; (3) the mechanism testing identifies population agglomeration, technological innovation, and the industrial structure as the three primary channels through which the HSRON exerts its influence; and (4) heterogeneity analysis reveals that the economic benefits are more pronounced in large cities with populations exceeding 5 million, resource-based cities, and cities within a 200 km radius of central cities.