Author(s)

Lembris Laanyuni Njotto

Department of Mathematics and ICT, College of Business Education, Dar Es Salaam, Tanzania.

Network is considered naturally as a wide range of different contexts, such as biological systems, social relationships as well as various technological scenarios. Investigation of the dynamic phenomena taking place in the network, determination of the structure of the network and community and description of the interactions between various elements of the network are the key issues in network analysis. One of the huge network structure challenges is the identification of the node(s) with an outstanding structural position within the network. The popular method for doing this is to calculate a measure of centrality. We examine node centrality measures such as degree, closeness, eigenvector, Katz and subgraph centrality for undirected networks. We show how the Katz centrality can be turned into degree and eigenvector centrality by considering limiting cases. Some existing centrality measures are linked to matrix functions. We extend this idea and examine the centrality measures based on general matrix functions and in particular, the logarithmic, cosine, sine, and hyperbolic functions. We also explore the concept of generalised Katz centrality. Various experiments are conducted for different networks generated by using random graph models. The results show that the logarithmic function in particular has potential as a centrality measure. Similar results were obtained for real-world networks.

Graph, Centrality Measures, Matrix Functions, Kendall Correlation Coefficient, Random Graph Models

Njotto, L. (2018) Centrality Measures Based on Matrix Functions. Open Journal of Discrete Mathematics, 8, 79-115. doi: 10.4236/ojdm.2018.84008.