Ecological efficiency evaluation based on data envelopment analysis and a dual-objective model

At present, for ecological efficiency evaluation, the traditional data envelopment analysis has the problem that the same model is difficult to take into account different proportions of economic and environmental efficiency analysis. This study innovatively proposes a dual-objective data envelopment analysis (DEA) ecological efficiency model that combines environmental efficiency and economic efficiency. This method is based on data inclusion analysis and addresses the limitations of traditional data envelopment analysis (DEA) in balancing economic and environmental efficiency ratios. The results showed that, compared to traditional methods, the new method considered cities with lower ecological efficiency more comprehensively. This was because it incorporated unexpected outputs, such as carbon emissions, and dynamic weight allocation. The provincial ENE was about 0.55 (new method), lower than the traditional data envelopment analysis’s 0.6, reflecting a more rigorous assessment of the model’s environmental impact. The environmental efficiency of a province was about 0.55, while the environmental efficiency of cities in the eastern, central, and western regions was about 0.75, 0.42, and 0.42, respectively. The environmental efficiency of cities in the north and south regions was around 0.35 and 0.73, respectively. The economic efficiency of the whole province was around 0.97, and the economic efficiency of the cities in the east, center, and west regions was around 0.99, 0.98, and 0.95, respectively, which were all higher than 0.95 and above. It demonstrated that the economic efficiency of the cities in the east, center and west regions was higher. The economic efficiency of cities in the north and south regions was around 0.965 and 0.995, respectively, and the economic efficiency of the province was higher at around 0.977. The ecological efficiency of the whole province was around 0.52. The ecological efficiency of cities in the east, center, and west regions was around 0.72, 0.41, and 0.42, respectively. The ecological efficiency of cities in the north and south regions was around 0.38 and 0.73, respectively. From 2020 to 2024, the changes in ecological efficiency in the province were more stable. The economic efficiency of all cities in the period from 2018 to 2020 was generally high, and some cities even reached a perfect score. It shows that the study proposes that the method can provide a new research idea for cracking the contradiction between resource environment and regional development.