The KED method (Chen et al. 2014) combines a node's degree \(k_i\) with the number and the diversity of the local paths that leave it. The local path number \(K_i = \sum_{j \in N(i)} k_j\) is the neighbors' degree sum, and the path diversity \(H_i\) is the entropy of the shares \(p_j = k_j / K_i\) divided by \(\log k_i\). $$KED_i = k_i \, (1 + H_i) \, \exp(K_i / N), \qquad H_i = \frac{-\sum_{j \in N(i)} p_j \log p_j}{\log k_i}$$
Arguments
- x
Network input accepted by
centrality.- ...
Further arguments to
centrality, such asnormalized.
Details
The measure is computed on the simple undirected skeleton of the network, so direction, weights, loops and parallel edges are ignored. The source's directed variant is not implemented. \(H_i\) lies in \([0, 1]\), and it is set to zero for a node with one neighbor, where it is \(0/0\). Isolates score zero. \(N\) is the number of nodes in the whole network, so adding a disconnected component changes every score and can change the ranking. The source's stated range \(1 \le \exp(K_i/N) \le e\) holds only when \(K_i \le N\), and an overflow of the exponential raises an error. The Centrality Zoo (section 2.215) adds exponents, drops the \(1 +\) term and divides by the largest \(K_l\). That form does not reproduce the scores printed in the source.
References
Chen, D.-B., Xiao, R., Zeng, A. and Zhang, Y.-C. (2014). Path diversity improves the identification of influential spreaders. Europhysics Letters, 104(6), 68006. doi:10.1209/0295-5075/104/68006 .
