title: Emergence of consensus as a modular-to-nested transition in communication dynamics.
abstract: Online social networks have transformed the way in which humans communicate and interact, leading to a new information ecosystem where people send and receive information through multiple channels, including traditional communication media. Despite many attempts to characterize the structure and dynamics of these techno-social systems, little is known about fundamental aspects such as how collective attention arises and what determines the information life-cycle. Current approaches to these problems either focus on human temporal dynamics or on semiotic dynamics. In addition, as recently shown, information ecosystems are highly competitive, with humans and memes striving for scarce resources -visibility and attention, respectively. Inspired by similar problems in ecology, here we develop a methodology that allows to cast all the previous aspects into a compact framework and to characterize, using microblogging data, information-driven systems as mutualistic networks. Our results show that collective attention around a topic is reached when the user-meme network self-adapts from a modular to a nested structure, which ultimately allows minimizing competition and attaining consensus. Beyond a sociological interpretation, we explore such resemblance to natural mutualistic communities via well-known dynamics of ecological systems.
authors.affiliation: Qatar Computing Research Institute, HBKU, Doha, Qatar.|Internet Interdisciplinary Institute (IN3), Universitat Oberta de Catalunya (UOC), Barcelona, Spain.|Institute for Biocomputation and Physics of Complex Systems (BIFI), Universidad de Zaragoza, 50018 Zaragoza, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Borge-Holthoefer
authors.affiliation: Institute for Biocomputation and Physics of Complex Systems (BIFI), Universidad de Zaragoza, 50018 Zaragoza, Spain.
authors.forename: Raquel A
authors.initials: RA
authors.lastname: Baños
authors.affiliation: Institute for Biocomputation and Physics of Complex Systems (BIFI), Universidad de Zaragoza, 50018 Zaragoza, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Gracia-Lázaro
authors.affiliation: Institute for Biocomputation and Physics of Complex Systems (BIFI), Universidad de Zaragoza, 50018 Zaragoza, Spain.|Department of Theoretical Physics, Faculty of Sciences, Universidad de Zaragoza, Zaragoza 50009, Spain.|Institute for Scientific Interchange (ISI), Torino, Italy.
authors.forename: Yamir
authors.initials: Y
authors.lastname: Moreno
mesh_terms: D001288:Attention; D003142:Communication; D003195:Computer Communication Networks; D032921:Consensus; D006801:Humans; D008962:Models, Theoretical