Digital industrialization, industrial digitalization and high-quality development in Chinese cities—analysis based on simultaneous equations of spatial panels

This study aims to investigate the mutual influences and spatial interactions among digital industrialization (DI, e.g. such as TikTok), industrial digitalization (ID, e.g. digital finance), and high-quality development (HQD) across Chinese cities, utilizing the Generalized Spatial Three-Stage Least Squares (GS3SLS) method. The main findings are as follows: (1) All three variables demonstrate significant positive spatial spillover effects. (2) Within the same city, DI, ID, and HQD mutually reinforce one another. Notably, ID contributes more substantially to HQD than DI does. Moreover, the influences of HQD on DI and that of ID on DI are both significantly stronger than reverse effects. (3) The determinants of DI and ID differ markedly. (4) Heterogeneity in the results is influenced by city scale and geographic location. Furthermore, the mediating effects of digital innovation, efficiency improvement, and industrial structure upgrading vary between DI and ID, also across the four regions. (5) The influence of ID on HQD and the feedback effect of HQD on ID exhibit threshold effects contingent on city population size. These results can help cities design better digital strategies based on their development stage and population size.