title: Urban characteristics attributable to density-driven tie formation.
abstract: Motivated by empirical evidence on the interplay between geography, population density and societal interaction, we propose a generative process for the evolution of social structure in cities. Our analytical and simulation results predict both super-linear scaling of social-tie density and information contagion as a function of the population. Here we demonstrate that our model provides a robust and accurate fit for the dependency of city characteristics with city-size, ranging from individual-level dyadic interactions (number of acquaintances, volume of communication) to population level variables (contagious disease rates, patenting activity, economic productivity and crime) without the need to appeal to heterogeneity, modularity, specialization or hierarchy.
authors.affiliation: Media Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Pan
authors.forename: Gourab
authors.initials: G
authors.lastname: Ghoshal
authors.forename: Coco
authors.initials: C
authors.lastname: Krumme
authors.forename: Manuel
authors.initials: M
authors.lastname: Cebrian
authors.forename: Alex
authors.initials: A
authors.lastname: Pentland
mesh_terms: D002947:Cities; D059066:Gross Domestic Product; D015658:HIV Infections / Q000453:epidemiology / Q000635:transmission; D006801:Humans; D008962:Models, Theoretical; D011156:Population Density; D012111:Residence Characteristics; D012959:Socioeconomic Factors; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D014505:Urban Population