# Topological Coefficient

#### Definition

Topological coefficient T

The topological coefficient is a relative measure for the extent to which a node shares neighbors with other nodes. Nodes that have one or no neighbors are assigned a topological coefficient of 0 (zero).

_{n}of a node n with k_{n}neighbors is the number of neighbors shared between a pair of nodes, n and m, plus one if there is a direct link between them, divided by the number of neighbors of node n: J(n,m) is defined for all nodes m that share at least one neighbor with n. The value J(n,m) is the number of neighbors shared between the nodes n and m, plus one if there is a direct link between n and m.The topological coefficient is a relative measure for the extent to which a node shares neighbors with other nodes. Nodes that have one or no neighbors are assigned a topological coefficient of 0 (zero).

#### Requirements

Require undirected network.

#### Software

#### References

- ASSENOV, Y., RAMÍREZ, F., SCHELHORN, S.-E., LENGAUER, T. & ALBRECHT, M. 2008. Computing topological parameters of biological networks. Bioinformatics, 24, 282-284.
- STELZL, U., WORM, U., LALOWSKI, M., HAENIG, C., BREMBECK, F. H., GOEHLER, H., STROEDICKE, M., ZENKNER, M., SCHOENHERR, A. & KOEPPEN, S. 2005. A human protein-protein interaction network: a resource for annotating the proteome. Cell, 122, 957-968.