## 3 Materials and Methods
### Index Selection
#### 3.2.1 Variable Determination
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Primary Variable** & **Secondary Variable** & **Resources of Variable** \\ \hline \multicolumn{4}{c}{(X6:1) Specific objects of S&T services} \\ \multicolumn{4}{c}{(Purchase content), (X6:2) Purchase mode,} \\ \multicolumn{4}{c}{(X6:3) Producers of S&T services} \\ \multicolumn{4}{c}{(Purchase object), (X6:4) Evaluation} \\ \multicolumn{4}{c}{and supervision} \\ \multicolumn{4}{c}{(X7:1) Law, (X7:2) Administrative} \\ \multicolumn{4}{c}{(X7) Effect level} \\ \multicolumn{4}{c}{(X7) Effect level} \\ \multicolumn{4}{c}{Normative document, (X7:5)} \\ \multicolumn{4}{c}{Industrial stipulation} \\ \multicolumn{4}{c}{(X8:1) Supply type, (X8:2) Demand type,} \\ \multicolumn{4}{c}{(X8:3) Environment type} \\ \multicolumn{4}{c}{(X9:1) Sufficient foundation, (X9:2) Clear} \\ \multicolumn{4}{c}{objectives, (X9:3) Detailed planning,} \\ \multicolumn{4}{c}{(X9:4) Scientific scheme} \\ \multicolumn{4}{c}{(X10:1) Standardization and guidance,} \\ \multicolumn{4}{c}{(X10:2) Institutional constraints, (X10:3)} \\ \multicolumn{4}{c}{Increasing the supply of S&T services,} \\ \multicolumn{4}{c}{(X10:4) Encouraging S&T innovation} \\ \hline \hline \end{tabular}
\end{table} 
Table 1: \(Cont.\)regional S&T innovation ability. GDP per capita is used to measure the regional economic level, which is recorded as _pgdp_. Degree of marketization. Regions with a higher degree of marketization usually have a more equal, tolerant and standardized market environment. Marketization environment improves regional S&T innovation ability through increasing market competition and reducing innovation cost. In this paper, the marketization index of each province in China which is calculated by [PERSON] et al. [9] is adopted to measure the degree of marketization and it is recorded as _market_. Level of opening up. Opening to the outside world is beneficial to introducing the foreign high-level technology. The introduction of advanced technology can realize cross-regional technology learning and limitation, improving the local S&T innovation ability [34; 35; 36]. This paper adopts the proportion of the import and export trade of the province to the regional GDP to measure the level of opening up, which is recorded as _open_. Human capital. Human capital is the key factor of regional S&T innovation. The proportion of population with a college degree or above in a region can directly reflect the structural characteristics of regional human capital [37]. Therefore, this proportion is taken as the proxy variable of human capital, which is recorded as _hc_. Level of R&D investment. The level of R&D investment is closely related to the S&T innovation ability. High level of R&D investment contributes to the allocation and supply efficiency of regional innovation resources, stimulating the vitality of regional S&T innovation and promoting regional S&T innovation ability [8]. The proportion of R&D expenditure to GDP of each province is applied to measure the level of R&D investment, recorded as _rdi_. Urbanization level. Urbanization is the process of spatial agglomeration of innovative elements such as industry and population. Urbanization can provide an active environment for the positive spillover of talents and technologies [38], and also promote governments to increase investments in innovation [20], thus laying a foundation for improving regional S&T ability. This paper uses the proportion of urban population in each province to measure the urbanization level, recorded as _urb_. Industrial structure. Regional industrial structure and S&T innovation are interrelated. The optimization and upgrading of industrial structure can provide a broad market for the application of S&T innovation [39], so as to improve regional S&T innovation ability. The industrial structure hierarchy coefficient is applied to measure this control variable [40], which is recorded as _is. is_\(=\sum\limits_{i=1}^{3}s_{i}*i\), where \(s_{i}\) is the proportion of the production in the \(i\)th industry to GDP.