## 2 Index System Construction, Research Methods and Data Sources
### Index System Construction of Industrial Green High-Quality Development and the Digital Economy
#### 2.1.2 The System of the Digital Economy  
Presently, research institutions have released the digital economy indicator system and measurement methods, such as the International Telecommunication Union, European Union, and Department of Commerce, and the China Center for Information Industry Development [39]. However, there are different standards for these measurement methods. Consistent with the needs of industrial green development, this paper develops indicator systems: the infrastructure of the digital economy, technological innovation, and industrial application of the digital economy. The infrastructure of the digital economy serves as the basis of industrial development, including new infrastructure and traditional infrastructure. Moreover, digital innovation leads to the transformation of industrial structure, including innovation input and innovation output, whereas digital application includes industrial digitalization and digital industrialization (see Table 1).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Target Layer** & **Criterion Layer** & **Indicator Layer** & **Attributes** \\ \hline \multirow{6}{*}{Industry Economy Benefits and Structure} & Rationalization of Industrial Structure & New Theil index & \multirow{2}{*}{\(-\)} \\  & Advanced Industrial Structure & The proportion of output value of & \\  & Advanced Industrial Structure & secondary and tertiary industries & \multirow{2}{*}{\(+\)} \\  & Labor Productivity & Regional production & \\  & & output/employment (yuan/person) & \\ \hline \multirow{6}{*}{Resource Consumption} & Energy Consumption & Energy consumption per ten thousand & \multirow{2}{*}{\(+\)} \\  & Resource Consumption & yuan of regional GDP (standard coal & \multirow{2}{*}{\(-\)} \\  & Water Consumption & Per capita water consumption & \(-\) \\ \cline{1-1}  & Land Consumption & Per capita land area & \(-\) \\ \cline{1-1}  & & Wastewater emissions from & \\ \cline{1-1}  & High-quality & 10,000 yuan of & \(-\) \\ \cline{1-1}  & Development & & gross regional product & \\ \cline{1-1}  & Environmental Pollution & Emissions of exhaust gases from & \multirow{2}{*}{\(-\)} \\ \cline{1-1}  & Environmental Pollution & 10,000 yuan of gross regional product & \\ \cline{1-1}  & Environmental pollution and Control & & Solid waste emissions from & \\ \cline{1-1}  & Environmental Pollution and Control & & 10,000 yuan of & \multirow{2}{*}{\(-\)} \\ \cline{1-1}  & & gross regional product & \\ \cline{1-1}  & The proportion of industrial pollution & & \\ \cline{1-1}  & Environmental Control & & control investment & \\ \cline{1-1}  & Environmental Control & & in industrial value added (\%) & \\ \cline{1-1}  & & Comprehensive utilization rate of solid & \multirow{2}{*}{\(+\)} \\ \cline{1-1}  & & waste (\%) & \\ \hline \hline \end{tabular}
\end{table}
Table 1: The Index System for Industrial Green High-quality Development and the Digital Economy.  
The stated indicators are weighted through the entropy method. The proposed method is a commonly used research method of scholars, therefore, this paper will not outline a detailed description. Besides, the calculation method can refer to the description of [PERSON] et al. [40].