How does new infrastructure affect urban innovation? A spatial spillover perspective

Moderately ahead of schedule layout and construction of new infrastructure (NI) is an important hand in grasping the opportunities of accelerated maturity of emerging technologies and industries in the current and future periods. This study explores the spatial spillover mechanism of NI on urban innovation (UI) by using the panel data of the Yangtze River Economic Belt from 2008 to 2021. The results are as follows: First, NI has a positive spatial spillover effect on UI. Second, the spillover effect of NI exhibits a geographic decay, with the strongest spillover effect between neighbouring cities and no spillover effect between cities in different provinces. Third, industrial agglomeration is a key factor influencing the spatial causality between NI and UI. Among them, diversified agglomeration and specialised agglomeration of information infrastructure have positive moderating effect on the spatial causality between NI and UI, specialised agglomeration of convergence infrastructure has negative moderating effect, and the moderating effect of specialised agglomeration of innovation infrastructure is not yet obvious. Fourth, the spillover effect of NI is released only at high UI levels or in the lower and upper reaches of the Yangtze River.