Identifying cliques in dark web forums - An agglomerative clustering approach

In this paper, we present a novel agglomerative clustering method to identify cliques in dark Web forums. Considering each post as an individual entity accompanying all the information about its thread, author, time-stamp, etc., we have defined a similarity function to identify similarity between each pair of posts as a blend of their contextual and temporal coherence. The similarity function is employed in the proposed clustering algorithm to group threads into different clusters that are finally presented as individual cliques. The identified cliques are characterized using the homogeneity of posts therein, which also establishes the homogeneity of their authors and threads as well.