Network nestedness as generalized core-periphery structures

Sang Hoon Lee

doi:10.1103/physreve.93.022306

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arXiv · 1602.00093

Network nestedness as generalized core-periphery structures

Sang Hoon Lee

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Abstract

The concept of nestedness, in particular for ecological and economical networks, has been introduced as a structural characteristic of real interacting systems. We suggest that the nestedness is in fact another way to express a mesoscale network property called the core-periphery structure. With real ecological mutualistic networks and synthetic model networks, we reveal the strong correlation between the nestedness and core-periphery-ness (likeness to the core-periphery structure), by defining the network-level measures for nestedness and core-periphery-ness in the case of weighted and bipartite networks. However, at the same time, via more sophisticated null-model analysis, we also discover that the degree (the number of connected neighbors of a node) distribution poses quite severe restrictions on the possible nestedness and core-periphery parameter space. Therefore, there must exist structurally interwoven properties in more fundamental levels of network formation, behind this seemingly obvious relation between nestedness and core-periphery structures.

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Sang Hoon Lee. 2016-02-19. Network nestedness as generalized core-periphery structures. https://doi.org/10.1103/physreve.93.022306

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