Evolution of Urban Green Innovation Efficiency Under Environmental Regulations: A Case Study of Xi'an

This paper aims to develop a method to properly measure the urban green innovation efficiency under environmental regulation, analyze the evolution rules of this efficiency, and make rational policy suggestions. By exploring an indicator system which is suitable for the actual urban development, we divided the urban green innovation process into interrelated sub-processes that are based on an innovation chain, established a slacks-based network DEA model, evaluated the overall efficiency of the urban green innovation system and the efficiency of each stage, and studied the evolution of urban green innovation efficiency. Taking Xi’an City as an example, we analyzed the evolution of urban green innovation efficiency under environmental regulation, with the results showing that the process of urban green innovation can be divided into two stages:technological innovation and technological conversion. Xi’an was at the forefront of green innovation efficiency only in 2006, 2009 and 2017, while making inefficient allocation of scientific resources in all other years. The efficiency of scientific and technological research and development has become a major factor in restricting the green innovation efficiency under environmental regulation in Xi’an. Forging ahead in both technological conversion and scientific innovation efficiency should be the best path of green development and innovation. To achieve the continuous and stable improvement of green innovation efficiency, Xi’an should keep improving its green innovation policy to adapt to the increasing social productive forces, and pay attention to the balance between technological innovation and technological conversion.