Fig. 10.

Geographical distribution of the influential sub-groups and the influential spreaders in population flow networks during phase two transmission in the population flow network. The degree centrality of some major cities had also decreased significantly, and the newly influential spreaders had been identified by removing these three cities, respectively. For example, when removing Guangzhou, the degree centrality of the top 3 cities with the biggest percentage decreases were Foshan (80.85% decrease), Nanning (23.53% decrease), and Shenzhen (21.45% decrease). Hangzhou had become the newly influential spreader, Beijing and Chongqing had changed into the well-characterized influential spreaders, while Foshan had not been the potential influential spreaders. When removing Chengdu, the degree centrality of the top 3 cities were Chongqing (39.00% decrease), Kunming (20.67% decrease), and Xining (14.23% decrease). Hangzhou also have become the newly influential spreader, while Chongqing had not been the influential spreaders. When removing Foshan, the degree centrality of the top 3 cities were Guangzhou (38.73% decrease), Nanning (14.64% decrease), and Shenzhen (10.19% decrease). Replaced Guangzhou, Beijing had become the well-characterized influential spreaders.