Applying a Ruggiero three-stage super-efficiency DEA model to gauge regional carbon emission efficiency: evidence from China

China's climate change mitigation strategies and efforts are based on accurate regional carbon emission efficiency (CEE) estimates. Decision-making units which are all data envelopment analysis (DEA)-effective cannot be ranked by using the original DEA model. While previous studies omit environmental factors when gauging resources or environmental efficiency. In this study, we combine a Ruggiero three-stage model with a super-efficiency DEA model (SE-DEA) to solve these two problems. Following this method, we consider environmental factors and thereby compare provincial CEE in China in the new production frontier. The main results obtained are as follows: (1) provincial CEE values differ significantly in the first stage and the third stage; (2) in the third stage, only Eastern China reaches the SE-DEA relatively effective level, where CEE rankings in descending order are: Eastern, Central, and Western China; (3) provinces are divided into four categories in terms of provincial CEE values and per-capita GDPs, and therefore, regional climate and development policies could be oriented due to different categories. This efficiency evaluation methodology and the results obtained in our study not only contribute to understanding this issue, but also could be of specific interest to climate change policy makers in China.