U.S. Social Fragmentation at Multiple Scales

TL;DR

This paper investigates the multi-scale social fragmentation in the U.S. by analyzing geo-located social media data, revealing geographically bounded social patches that mirror offline divisions and are reinforced through online interactions.

Contribution

It introduces a multi-scale analysis of social fragmentation using social media data and proposes a network growth model explaining patch emergence based on geographical and preferential attachment mechanisms.

Findings

Identifies geographically bounded social patches at multiple scales.

Shows virtual social borders mirror offline divisions.

Proposes a network growth model explaining patch formation.

Abstract

Despite global connectivity, societies seem to be increasingly polarized and fragmented. This phenomenon is rooted in the underlying complex structure and dynamics of social systems. Far from homogeneously mixing or adopting conforming views, individuals self-organize into groups at multiple scales, ranging from families up to cities and cultures. In this paper, we study the fragmented structure of the American society using mobility and communication networks obtained from geo-located social media data. We find self-organized patches with clear geographical borders that are consistent between physical and virtual spaces. The patches have multi-scale structure ranging from parts of a city up to the entire nation. Their significance is reflected in distinct patterns of collective interests and conversations. Finally, we explain the patch emergence by a model of network growth that combines mechanisms of geographical distance gravity, preferential attachment, and spatial growth. Our observations are consistent with the emergence of social groups whose separated association and communication reinforce distinct identities. Rather than eliminating borders, the virtual space reproduces them as people mirror their offline lives online. Understanding the mechanisms driving the emergence of fragmentation in hyper-connected social systems is imperative in the age of the Internet and globalization.