Table 2.

Main network metrics of graph theory.

Metrics	Definition/meaning
Average path length	The average of the distances of all point pairs in the network.
Clustering coefficient	The ratio of the number of edges between a node and its neighbors to the maximum possible number of edges.
Global efficiency	Measure the information transmission capacity between nodes in the network.
Local efficiency	The global efficiency of the sub-network formed by the interaction of each neighbor.
Node degree	The number of connections that link it to the rest of the network.
Betweenness	The contribution of each node to the shortest path between all other pairs of points.
Nodal efficiency	Information transmission capacity of each node in the network.
Robustness	The ability of a network to maintain its typical network characteristics after removal of specific node(s) or edge(s).