1. Asim A, Nasar R, Rashid T (2019) Correlation coefficient of intuitionistic hesitant fuzzy sets based on informational energy and their applications to clustering analysis. Soft Comput 23:10393–10406
2. Chen W (2016) China’s demographic estimation using the generalized stable population model. Popul J 38(1):5–13
3. Chen MH, Hao GC (2014) Research on regional difference decomposition and influence factors aging in China. China Popul Resour Environ 24(4):136–141
4. Chen YG, Yu B (2006) Three models for predicting population growth—theoretical foundation, application methods, and revised expressions. J Central China Normal Univ (Nat Sci) 40(3):452–456
5. Chen YH, Li YS, Su CG (2012) Radial basis function neural network model applied in the forecast of population aging taking Hunan Province as an example. Econ Geogr 32(4):34–39