Transportation infrastructure and economic growth: Evidence from "new nighttime light data" in the Yangtze River Delta

The enhancement and improvement of China's high-speed rail network plays a crucial role in promoting sustainable economic growth in the region. By utilizing "new nighttime light data" in China's Yangtze River Delta from 2003 to 2018, this paper investigates the impact of HSR on economic growth using a multiperiod difference-in-differences (DID) model. The operations of high-speed rail have a significant and positive impact on economic growth, which often becomes more apparent with a certain time delay. The operations of high-speed rail have a significant positive impact on the development of large, mega, and super-cities, with this impact becoming more pronounced as the size of the city increases. Furthermore, high-speed rail operations have a significant influence on the economic growth of cities that largely rely on secondary and tertiary industries, in contrast to the primary industry. The promotion of economic growth by high-speed rail is primarily achieved through three transmission channels: low carbon emissions, labor force agglomeration, and innovation. Over time, high-speed rail will progressively reduce economic disparities between regions and facilitate a trend towards regional economic coordination or convergence. This study makes a valuable contribution to the exploration of pathways towards achieving economic growth.