Complex Networks and Symmetry II: Reciprocity and Evolution of World Trade

Franco Ruzzenenti; Diego Garlaschelli; Riccardo Basosi

doi:10.3390/sym2031710

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arXiv · 1009.4489

Complex Networks and Symmetry II: Reciprocity and Evolution of World Trade

Franco Ruzzenenti·Diego Garlaschelli·Riccardo Basosi

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Abstract

We exploit the symmetry concepts developed in the companion review of this article to introduce a stochastic version of link reversal symmetry, which leads to an improved understanding of the reciprocity of directed networks. We apply our formalism to the international trade network and show that a strong embedding in economic space determines particular symmetries of the network, while the observed evolution of reciprocity is consistent with a symmetry breaking taking place in production space. Our results show that networks can be strongly affected by symmetry-breaking phenomena occurring in embedding spaces, and that stochastic network symmetries can successfully suggest, or rule out, possible underlying mechanisms.

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Franco Ruzzenenti, Diego Garlaschelli, Riccardo Basosi. 2010-09-22. Complex Networks and Symmetry II: Reciprocity and Evolution of World Trade. https://doi.org/10.3390/sym2031710

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