2.4.6. Neighbor-Sum Centrality

Nsum(i) emphasizes whether the neighbors of node i are influential, defined as the sum of weight-sum Wsum(j) for all neighbors j.

where V(i) is the set of nearest neighbors of node i. In the weighted adjacency matrix wij, the number of nearest neighbors is equal to the number of non-zero elements in row i or column j of the node.