OvSbChain: An Enhanced Snowball Chain Approach for Detecting Overlapping Communities in Social Graphs

Overlapping Snowball Chain is an extension to Snowball Chain, which is based on the concept of community formation in line to the snowball chaining process. The inspiration behind this approach is from the snowball sampling process, wherein a snowball grows to form chain of nodes, leading to the formation of mutually exclusive communities in Snowball Chain. In the current work, the nodes are allowed to be shared among different snowball chains in a graph, leading to the formation of overlapping communities. Unlike its predecessor Snowball Chain, the proposed technique does not require the use of any hyper-parameter which is often difficult to tune for most of the existing methods. The proposed algorithm works in two phases, where overlapping chains are formed in the first phase, and then they are combined using a similarity-based criteria in the second phase. The communities identified at the end of the second phase are evaluated using different measures, including modularity, overlapping NMI and running time over both real-world and synthetic benchmark datasets. The proposed Overlapping Snowball Chain method is also compared with eleven state-of-the-art community detection methods.