in each network were selected with a rank order according to their centrality. Then, Spearman’s rank
correlation coeﬃcient was used to examine the correlation of the rank orders of the selected nodes
in the two discourses [84], where a high Spearman correlation indicates that the hashtags in the two
discourses were ranked similarly. Secondly, we measured to what extent the two discourses resembled
each other in the associations between the key hashtags for each year. For every year, we obtained the
union of the two top 50 nodes lists and used the name of the nodes in the union as the row name and