Table 4 Formal Representation of Graph Measures.

From: Computational characterization and identification of human polycystic ovary syndrome genes

Name

Function

Descriptions

Degree

\({{\rm{K}}}_{{\rm{i}}}^{1}\)

the number of direct interaction partners of node i

Degree-2

\({{\rm{K}}}_{{\rm{i}}}^{2}\)

the number of 2-step interaction partners of node i

1st PCOS ratio

\({{\rm{K}}}_{{\rm{i}}}^{1,{\rm{P}}}/{{\rm{K}}}_{{\rm{i}}}^{1}\)

\({{\rm{K}}}_{{\rm{i}}}^{1,{\rm{P}}}\) is the number of direct interactions between node i and proteins encoded by PCOS genes

2nd PCOS ratio

\({{\rm{K}}}_{{\rm{i}}}^{2,{\rm{P}}}/{{\rm{K}}}_{{\rm{i}}}^{2}\)

\({{\rm{K}}}_{{\rm{i}}}^{2,{\rm{P}}}\) is the number of 2-step interaction between node i and proteins encoded by PCOS genes

Betweenness

\(\sum _{\begin{array}{c}j\in V,k\in V\\ j\ne i,k\ne i\end{array}}\frac{\sigma (j,i,k)}{\sigma (j,k)}\)

\(\sigma (j,I,k)\) is the total number of shortest connections between nodes j and k, where each shortest connection has to pass node i, and \(\sigma (j,k)\) is the total number of shortest connections between j and k. The set V of nodes represents all proteins in the network.

K-core

K

A K-core of a graph can be obtained by recursively removing all nodes with a degree less than K, until all nodes in the remaining graph have a degree at least K.

  1. Functions are the definitions of the topological features. Descriptions give explanations for symbols in the definitions.