A study on the temporal evolution characteristics and correlation between China's coal industry prosperity index and just transition

Against the backdrop of China’s dual-carbon goals and supply-side structural reform, the coal industry is undergoing profound industrial restructuring, with just transition emerging as a critical issue. This study explores the relationship between the economic conditions of the coal industry and the just transition. Indicator systems for the China coal industry prosperity index and the just transition index are constructed, and the composite index method is used to measure both indices and analyze their temporal evolution. A coupling coordination degree model is employed to examine the relationship between the two indices. Furthermore, the XGBoost regression algorithm, combined with SHAP value decomposition, is introduced to identify key indicators within the coal industry prosperity index that are strongly associated with the just transition. The robustness of the empirical results is examined through model stability tests and questionnaire surveys. The results show that: (1) The just transition index demonstrates an overall upward trend during the study period, while the coal industry prosperity index exhibits phased fluctuations, indicating gradual improvement in fairness during the transformation process. (2) The coupling coordination degree between coal industry prosperity and just transition increases overall, suggesting a strengthening relationship between the two. (3) The contributions of coal industry prosperity indicators exhibit clear structural differentiation: profitability indicators show the highest contribution, investment and revenue indicators provide important support, whereas scale and price indicators contribute relatively less. (4) Robustness tests and questionnaire analysis further confirm the stability of the empirical findings. These findings provide policy-relevant insights for promoting a just transition in the coal industry.