Spatial Improvement Of DEA And Its Application In Urban Efficiency Evaluation

The National New Urbanization Plan states that “China is in a critical period for the in-depth development of urbanization.” In 2019,the National Development and Reform commission also explicitly requires “accelerating the implementation of the new urbanization strategy oriented by improving quality”.The mode of urban development must shift from speed and scale to efficiency and quality,that is,to achieve high-quality urban development.Urban efficiency is a comprehensive reflection of high-quality urban development.It is of great significance to reconstruct urban input-output index system and evaluate urban efficiency for promoting highquality urban development through efficiency change.Among the existing urban efficiency evaluation methods,data envelopment analysis(DEA)is widely used because of its unique advantages.DEA is a kind of nonparametric technical efficiency analysis method.Since the DEA method was put forward,the theory and method of DEA have developed rapidly,the scope of application has been expanding,and the number of applications has maintained a continuous growth trend.However,in the process of urban development,more and more elements are absorbed,and it has evolved into a complex and multilevel system.With the development of regional integration,the urban network system is gradually formed and strengthened,and the competition effect and complementary effect between cities exist at the same time.The strengthening of this multidimensional spatial connection leads to the gradual exposure of the defects of ignoring the spatial function in the process of using the traditional DEA method for urban efficiency evaluation,so it is necessary to improve the relevant urban efficiency evaluation method.Based on the above problems,this paper introduces the concept of spatial interaction between cities on the basis of the traditional DEA model,uses the tool of geographic detector,combines with the modified gravity model,reconstructs the evaluation set in the traditional DEA model by relying on the degree of spatial connection between cities,finally realizes the spatial improvement of the DEA model,and puts forward the S-DEA efficiency evaluation method.In this paper,the main cities in the Yellow River Basin and the Yangtze River Delta region are taken as examples to compare the evaluation results of traditional DEA method and S-DEA method.It is proved that the evaluation results of S-DEA method have more practical reference significance in the study of regional efficiency evaluation.It has three characteristics:(1)The efficiency value of s-dea is generally higher than that of DEA,and the evaluation conclusion of city is more optimistic than that of DEA;(2)In the evaluation results,the optimal efficiency city of urban reference is more relevant,which is not only reflected in the approach of spatial location,but also in the similarity of the development scale of the city itself;(3)The improvement suggestions given by s-dea method are consistent with the actual development of the city,and the adjustment pressure is relatively small in the later stage of the city.Then,based on the evaluation results of S-DEA method,this paper analyzes the efficiency improvement of the cities in the two study areas from three dimensions of urbanization construction,ecological environment construction and economic development,puts forward seven types of urban efficiency improvement,and puts forward some suggestions for regional urban development according to the regional characteristics.