An empirical study on air transport promoting the coordinated regional economic development: A perspective of spatial interaction

This result holds after addressing endogeneity via instrumental variable estimation and a battery of rigorous robustness checks. Second, we identify spatial interaction as the core mediating mechanism: descriptive evidence confirms it is the primary pathway linking air transport to CRED. Third, inter-regional factor circulation acts as a significant moderating condition: the positive association between air transport and CRED is stronger when the factor endowment gap between region-pairs is smaller.

Fourth, heterogeneity analyses show that air transport’s positive effect on CRED is more pronounced for region-pairs covering Central-South, North China, and East China, and that this effect gradually weakens over the sample period.