Figure 4. Calculation of the clustering coefficient (C).

The links between node i and other nodes in the network defines the neighborhood of node i (A). Node i has 8 links, or “neighbors”, denoted as k_i. To calculate the clustering coefficient for node i (C_i), we find the number of possible unique connections between the neighbors (k_i) using the formula [k_i(k_i−1)/2], or in this case (8*7)/2 = 28. We then find the number of actual connections (Δ _i) between neighbors, in this case 5 (B). C_i is simply defined as the actual links (Δ _i) divided by the possible links [k_i(k_i−1)/2] in the neighborhood of node i. Therefore, C_i = 2Δ _i/(k_i−1)k_i = 0.178 [40].