title: Modes of interaction between individuals dominate the topologies of real world networks.
abstract: We find that the topologies of real world networks, such as those formed within human societies, by the Internet, or among cellular proteins, are dominated by the mode of the interactions considered among the individuals. Specifically, a major dichotomy in previously studied networks arises from modeling networks in terms of pairwise versus group tasks. The former often intrinsically give rise to scale-free, disassortative, hierarchical networks, whereas the latter often give rise to single- or broad-scale, assortative, nonhierarchical networks. These dependencies explain contrasting observations among previous topological analyses of real world complex systems. We also observe this trend in systems with natural hierarchies, in which alternate representations of the same networks, but which capture different levels of the hierarchy, manifest these signature topological differences. For example, in both the Internet and cellular proteomes, networks of lower-level system components (routers within domains or proteins within biological processes) are assortative and nonhierarchical, whereas networks of upper-level system components (internet domains or biological processes) are disassortative and hierarchical. Our results demonstrate that network topologies of complex systems must be interpreted in light of their hierarchical natures and interaction types.
authors: Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Korea.
authors: Insuk
authors: I
authors: Lee
authors: Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Korea.
authors: Eiru
authors: E
authors: Kim
authors: Center for Systems and Synthetic Biology, Department of Molecular Biosciences, and Institute for Cellular and Molecular Biology, MBB 3.148BA, University of Texas at Austin, 2500 Speedway, Austin, Texas 78712-1064, United States of America.
authors: Edward M
authors: EM
authors: Marcotte
mesh_terms: D006801:Humans; D007398:Interpersonal Relations; D012919:Social Behavior; D060756:Social Networking