[Table 1]

2.4 Evaluation of urbanization level

2.4.1 Selection of urbanization indicators

Referring to some related literatures (such as Liu, 2018; Li, 2021), we constructed an urbanization assessment system based on the entropy value method from four aspects (Table 2). The comprehensive UI system coordinates with 4 primary indicators and 10 secondary indicators. Population urbanization (PU) is the baseline of urbanization development, which is characterized by the population density and the urban population proportion. As the core content of urbanization development, economic urbanization (EU) is characterized by GDP, secondary and tertiary industries proportions, and total fixed asset investment. Spatial urbanization (SU) is characterized by urban road area and urban construction land proportions. Social urbanization (SCU) denates the diffusion of civilization and the level of people’s living standards, enriching the connotation of urbanization, and is characterized by average wage of staff and workers employed in urban units and total sales of social consumer goods.