In graph theory, a clustering coefficient is a measure of the extent to which nodes in a graph tend to cluster together. A triplet consists of three nodes that are connected by either two (open triplet) or three (closed triplet) undirected ties. A triangle consists of three closed triplets, one centred on each of the nodes.
The global clustering coefficient is the number of closed triplets (or 3 x triangles) over the total number of triplets (both open and closed). It provides an overall indication of the clustering in the network.