Research On The Evolution Characteristics And Multi-dimensional Mechanism Of The Urban Network Structure In The Yangtze River Delta-from The Perspective Of Digital Economy Enterprises

With the rapid development of the new generation of information technology,the digital economy has gradually become a way to enhance the competitiveness of cities,accelerate the flow of regional factors,and achieve high-quality economic development.The digital economy may change the original urban system.As one of the regions with the highest degree of openness and activity in China,the Yangtze River Delta region is experiencing rapid development of the digital economy.Exploring the evolution characteristics and formation mechanism of the urban network structure in the Yangtze River Delta region has an important impact on optimizing the coordination of industrial division of labor in the Yangtze River Delta region and realizing regional integration.This study takes 210 counties in the Yangtze River Delta region as the research object.Based on the corporate headquarters-branch data of the national economic censuses in 2008,2013,and2018,constructs the urban network of enterprises,digital economy manufacturing enterprises,and digital economy service enterprises.This study uses the social network analysis method to explore the spatial and temporal evolution characteristics of the Yangtze River Delta city network,and uses QAP method to analyse the mechanism of the formation of the digital economy city network.The research found that:(1)With the rapid development of urban networks based on the digital economy,the number and intensity of node connections and city-to-city connections have increased,showing the evolution characteristics of "dense in the east and sparse in the west,layered agglomeration".(2)The whole digital economy network density is constantly increasing,and the network structure is constantly improving.The density of the digital economy manufacturing network is low,and the level of network development is far inferior to that of the digital economy service industry.(3)Among the node characteristics of the urban network,the point-degree centrality,weighted centrality,and betweenness centrality all show the evolution characteristics from the polarized distribution of provincial urban areas to the multi-center hierarchical distribution.The degree of spatial agglomeration of weighted centrality is higher than betweenness centrality and point-degree centrality;the degree of agglomeration of out-degree centrality is higher than that of in-degree centrality;the degree of centrality polarization of digital economy manufacturing is higher than that of the digital economy.(4)There is a certain degree of industry heterogeneity in the community division of urban networks.The whole digital economy network mainly forms four major network communities with the province as the boundary,the digital economy manufacturing industry forms a number of small network communities,and the digital economy service industry forms three large network communities and three small network communities.(5)Differences in economic scale,administrative level,industrial structure,and geographical distance between cities will significantly hinder the formation of urban networks,while urban population size,administrative divisions,and previous network connections will promote the formation of urban networks effect.The significance level of government intervention is weak.The influencing factors have heterogeneity in different networks.The influence of geographical distance on the manufacturing network of the digital economy is disappearing,and the urban network of the digital economy service industry has broken through the restrictions of administrative boundaries.