Expert decision-based DEA cross-efficiency model and its application to the analysis of energy utilisation efficiency in Chinese cities

Achieving the goal of “dual carbon” is a major initiative of the Chinese government to promote sustainable development, and improving urban energy utilisation efficiency (EUE) is crucial to achieving this goal. As an important tool for EUE analysis, the Data envelopment analysis (DEA) cross-efficiency (CE) method has the following shortcomings: first, the DEA-CE model requires that each decision-making unit (DMU) be provided with a weight, which is inconsistent with the reality of efficiency evaluation. Second, the CE weights are given to maximise the efficiency of the evaluated DMU, which is difficult to be consistent with the decision-making objective. Finally, the DEA-CE model cannot well satisfy multiple returns to scale (RTS) situations. To this end, this paper first proposes a DEA-CE model and cross-projection method based on expert decision-making and extends it to apply to the case of multiple RTS. Then, the method of this paper and the DEA-CE model are applied to conduct a comparative analysis of EUE in Chinese cities. The results show that the method in this paper demonstrates strengths in evaluating subjects, reflecting decision objectives, and satisfying multiple returns to scale scenarios.