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The Theta index measures the function of a node, that is, the average amount of traffic per intersection. The higher the index is, the greater the load of the network. The measure can also be applied to the number of links (edges).

Eta is the average length per link. Adding new nodes will cause a decrease in Eta as the average length per link declines.

Source: Adapted from Kansky (1963), p. 23. The Pi index is the ratio between the diameter (d; vertical axis) and length of the network (horizontal axis). A low Pi index is linked with a low level of network development (such as simple corridors), and a high value of Pi is

The physical attributes of space, such as the topography, influence the route selection process since they impose a variable friction on movements. Consequently, a route between two locations (1 and 3, but also using intermediate location 2) may use a path that is not necessarily the most direct, but less

The cost in a graph represents the total length of the network measured in real transport distances where aij is the presence (1) or absence (0) of a link between i and j and lij is the length of the link. This measure can also be calculated based on two other

The maximum number of independent cycles in a graph (u) is estimated through the number of nodes (v), links (e) and of sub-graphs (p). Trees and simple networks have a value of 0 since they have no cycles. The more complex a network is, the higher the value of u,

A, B, C, and D graphs have respective diameters of 2, 3, 4, and 3. Adding a link on graph C between nodes 4 and 6 reduced the diameter by 1 (graph D).

The diameter of a graph is the length of the shortest path between the most distanced nodes. d measures the extent of a graph and the topological length between two nodes. The number of links (edges) between the furthest nodes (2 and 7) of the above graph is 4. Consequently,

On this graph, link (3,4) is an isthmus since removing the link creates two connected subgraphs. Link (4,5) is not an isthmus since removing the link does create two subgraphs, but one graph is composed of only one node (5).