Urban shrinkage is a global phenomenon, and it will coexist with urban growth for many years. At the same time, the network connection between cities continuously improved due to the construction of the transportation and information networks. However, the relationship between urban network externalities and urban population growth/shrinkage remains unclear. Therefore, based on high-speed railway (HSR) flow data, a spatial econometric model is used to explore the mechanism behind urban population growth and shrinkage from the perspective of net...