Characteristic path length (L) is the average shortest path length (i.e., the minimal number of edges that form a direct connection between two nodes) between all pairs of nodes in the network and is a measure of functional integration. A short L indicates a more compact network and more efficient global information processing. |
Global efficiency (Eglob) is the average inverse shortest path length between all pairs of nodes in the network and is a measure of functional integration, and represents the functional efficiency of brain networks for information transmission between multiple parallel paths. |
Transitivity (T) is the ratio of triangles to triplets in the network, and was a measure of clustering or functional segregation. |
Modularity (M) quantifies how well the network can be subdivided into non-overlapping groups of nodes or modules and is a measure of functional segregation. |
Node-level measures |
Clustering coefficient (C) is a measure of the number of edges between a node’s nearest neighbors or the fraction of triangles around a node, and is a measure of functional segregation. High C represents clustered connectivity at the node. |
Local efficiency (Eloc) is the global efficiency computed on node neighborhoods, is related to C, and is a measure of functional segregation. |
Degree (d) is the number of edges connected to a node, and provides information related to the centrality of a node by determining nodes with a large number of connections. |
Betweenness centrality (CB) is the fraction of all the shortest paths in the network that contain a given node. Nodes with high CB participate in a large number of shortest paths and may connect distinct parts of the network. |
Participation coefficient (P) is a measure of the inter-modular connections of nodes and indicates centrality. |