The existing distance and similarity measures of hesitant fuzzy linguistic term sets (HFLTSs) only cover the difference of linguistic terms but have no consideration of the difference between the numbers of linguistic terms. Thus, the concept of hesitance degree of HFLTSs is introduced to describe the hesitant degree among several linguistic terms in each HFLTS during the decision-makers' evaluating process. Considering the hesitance degree of HFLTSs, several novel distance and similarity measures of HFLTSs are developed, and their properties are discussed. Afterward, a novel hesitant fuzzy linguistic-based on the novel similarity measures and the Boole matrix is developed to classify the objects with hesitant fuzzy linguistic information and a numerical example of the automobile recommendation is given to illustrate the performance of our developed clustering method. The results indicate that our developed clustering method can fully express the original evaluation information and has less computational effects on clustering results than the previous method.

The resilience of the fiscal system has a driving effect on environmental governance, and it is always a challenge to solve the problem of matching fiscal power with administrative power. Based on the panel data of 193 cities in China from 2013 to 2018, the data envelopment analysis method was used to evaluate the comprehensive indicators of urban environmental efficiency. The impact of fiscal stress on environmental efficiency is examined from the perspective of urban horizontal imbalance. We find that the smaller the fiscal stress, the higher urban environmental efficiency. The endogeneity is mitigated by using instrumental variables and the generalized method of moments, and the results are still robust after considering the interference of sample selection bias and variable estimation bias. At the same time, the impact of fiscal stress on environmental efficiency varies with spatial location, ecological strategic planning, economic development, and other factors, especially in southern cities, cities in the Yangtze River Basin, and cities in urban agglomerations, where reducing fiscal stress promotes environmental efficiency. In addition, green production and public environmental services are important channels for its role, and the rational allocation of self-raised funds can effectively moderate the improvement of environmental efficiency.