How to improve the performance of China's energy-transport-economy-environment system: An analysis based on new strategy parallel-series input-output data envelopment analysis models

To the best of our knowledge, all the existing input-output data envelopment analysis (IO-DEA) models adopt parallel structures, without further distinguishing two different production processes (interindustry transaction and value-added). In this regard, overlooking the differences between two production processes may obtain misleading results. To overcome the deficiency, this study develops a new parallel-series IO-DEA model to capture the complex relationships and interactions of two production processes. Furthermore, this study proposes a new framework to perform efficiency analysis and relative priority analysis. Empirically, this study focuses on the energy-transport-economy-environment system in China at national level and provincial level. Such work cannot be found in the existing studies. The main conclusions are summarized as follows. First, there are sig-nificant differences between two stages in efficiency-related measures, showing that our new parallel-series model can provide fresh insightful information. Second, China has experienced an overall efficiency regress of energy-transport-economy-environment system and such regress is mainly induced by value-added stage and two sectors (energy and economy sectors). Third, among all sectors, economy sector attracts the highest priority and then it is followed by transport sector. Finally, alternative strategies generate significant impacts on efficiency-related measures. Importantly, strategies tend to reduce overall efficiency, but well-suited one can improve ef-ficiency for some decision-making units.