## 4 Measurement Estimation and Analysis
### Robustness Test
#### 4.4.2 The Analysis of the Regression Results of Eastern, Central, and Western Regions
\begin{table}
\begin{tabular}{c c c c c c c} \hline  & \multicolumn{2}{c}{**(1) The Yangtze**} & \multicolumn{2}{c}{**(2) The Pearl**} & \multicolumn{2}{c}{**(3) Beijing-**} & \multicolumn{2}{c}{**(4) Northeastern**} & \multicolumn{2}{c}{**(5) Chengdu-Chongqing**} \\  & & **River Delta** & **River Delta** & **Region** & **Region** & **Region** & **Economic Circle** \\ \hline \multirow{10}{*}{The Direct Effect} & \multicolumn{2}{c}{**InAEP**} & **InAEP** & **InAEP** & **InAEP** & **InAEP** & **InAEP** \\  & LR\_Direct & & & & & & \\  & wlnAPI & 1.214 & 1.988 & \(-\)4.253 *** & 0.377 & 0.949 \\  & & (1.269) & (0.656) & (\(-\)2.824) & (0.335) & (0.426) \\  & Iner & \(-\)0.271 *** & \(-\)0.041 & \(-\)0.171 & \(-\)0.073 * & \(-\)0.079 \\  & & \((-\)5.519) & \((-\)0.518) & (\(-\)1.428) & (\(-\)1.650) & (\(-\)1.059) \\  & Inden & 0.187 & 0.112 & \(-\)0.133 & 0.089 & \(-\)0.131 \\  & & (1.470) & (0.502) & (\(-\)0.608) & (0.894) & (\(-\)1.568) \\  & Inhua & 0.055 & \(-\)0.468 & (0.219) & 0.151 & \(-\)1.783 *** \\  & & (0.490) & (\(-\)1.162) & (1.000) & (0.674) & (\(-\)6.309) \\  & Iney & \(-\)1.512 *** & \(-\)1.518 *** & \(-\)1.743 *** & \(-\)2.898 *** & \(-\)0.123 \\  & & (\(-\)1.2497) & (\(-\)5.798) & (\(-\)6.805) & (\(-\)11.745) & (\(-\)1.105) \\  & Inxin & \(-\)2.299 *** & \(-\)5.136 *** & 2.208 *** & 2.891 *** & \(-\)1.822 *** \\  & & (11.866) & (6.009) & (4.113) & (6.964) & (\(-\)4.237) \\  & \(N\) & 574 & 126 & 182 & 490 & 266 \\  & \(R^{2}\) & 0.537 & 0.654 & 0.783 & 0.443 & 0.209 \\ \hline \multirow{10}{*}{The Indirect} & LR\_Indirect & & & & & \\ \cline{1-1}  & wlnAPI & 8.821 * & 3.905 & \(-\)15.210 *** & 0.780 & \(-\)20.482 \\ \cline{1-1}  & Iner & \((-\)1.734) & (0.673) & (\(-\)2.807) & (0.325) & (\(-\)1.600) \\ \cline{1-1}  & Iner & \(-\)1.090 *** & \(-\)0.507 * & \(-\)1.620 *** & \(-\)0.149 & 0.390 \\ \cline{1-1}  & & (-\)2.899) & (\(-\)1.825) & (\(-\)3.821) & (\(-\)1.036) & (0.871) \\ \cline{1-1}  & Inden & 3.354 *** & \(-\)0.055 & \(-\)0.333 & 0.042 & \(-\)0.172 \\ \cline{1-1}  & & (3.706) & (\(-\)0.088) & (\(-\)0.469) & (0.180) & (\(-\)0.542) \\ \cline{1-1}  & & 1.507 * & \(-\)1.312 & 1.398 & 1.040 & \(-\)1.006 \\ \cline{1-1}  & & (7.900) & (\(-\)0.814) & (1.420) & (1.429) & (\(-\)0.710) \\ \cline{1-1}  & Iney & \(-\)0.525 & 0.383 & 0.888 & 0.056 & \(-\)0.020 \\ \cline{1-1}  & & (\(-\)0.933) & (0.570) & (1.132) & (0.134) & (\(-\)0.032) \\ \cline{1-1}  & & 8.346 *** & 9.199 *** & 3.076 * & \(-\)0.718 & \(-\)0.632 \\ \cline{1-1}  & & (3.633) & (3.881) & (2.503) & (\(-\)1.180) & (\(-\)0.336) \\ \cline{1-1}  & & 574 & 126 & 182 & 490 & 266 \\ \cline{1-1}  & & \(R^{2}\) & 0.537 & 0.654 & 0.783 & 0.443 & 0.209 \\ \hline \end{tabular}
\end{table} 
Table 10: _Cont._manufacturing. On the other hand, corporate investment to green technology innovation remained inadequate, and unreasonable industrial structure became an important factor that aggravated environmental pollution in the central region. Subject to environmental regulation, governments guide enterprises in the central region to advance technological innovation, increase environmental taxes on highly polluting industries, and realize the coordination between environmental protection and economic growth. Yet, owing to the low level of economic development in the central region, technological innovation and industrial-structure transformation lag behind atmospheric environmental pollution and lead to serious environmental pollution.