Evaluation of Cities' Green Economy Efficiency and Empirical Reasearch in Hercynian Economic Zone: Based on Entropy Method and DEA Model

To alleviate the contradiction between economic development and environmental pollution, and promote the green economy actively has become the focus of discussion. This paper takes Hercynian cities as its research area, conducts Entropy method for environmental pollution index, and lastly calculating the relatively green GDP. Then it takes labor, capital, water resources, energy as the input indexes of economy, and takes the relatively green GDP as output indicators, uses DEA-BCC and DEA-Malmquist model, makes empirical measure and studies of green economy efficiency of Hercynian's 20 cities from 2003 to 2015. And it turns out that:(1) The effective Heiseynian city of the DEA has been gradually shifted from the east coast to the south and the northeast, and the overall efficiency has increased in 13 years. (2) The technical efficiency of Hercynian cities is not significant in 13 years, and the technological change is the main factor that restricts the comprehensive efficiency of Hercynian cities.