Fig. 3: Regional impact of AI on NS via panel regression analysis.
A–C Demonstrate the influence of AI on NS across the west, central, and east, respectively, based on eight representative regression models. The slopes of the lines indicate the effect of AI on NS (βi, where i = 1, 2, 3) in each region. The shaded regions around the line correspond to the 95% confidence interval for the base model (model 3). Below each graph, bars illustrate the distribution of AI penetration levels across the regions. Annotations include “FE” for models incorporating fixed effects to control for unobserved, time-invariant differences among units, and “w/o control vars” to denote models executed without additional control variables. The dotted line represents the estimated effect after applying a 2% truncation to the variables, used to mitigate the influence of extreme observations. D–F Present the temporal dynamics of AI effects on NS over consecutive 5-year intervals throughout three regions, spanning the same 2006–2020 period. G Comparison of the fitting coefficients in China and the three regions achieved from 8 different models.
