The Diffusion and Reach of Information on Social Media

• In Event: Political Parties and American Democracy Mini-Conference III: How the Public Used Facebook and Instagram in the 2020 U.S. Election

Abstract

Social media create the possibility for rapid, viral spread of content. We analyze the virality of and exposure to information on Facebook during the US 2020 Presidential election by examining the diffusion trees of the approximately 1B posts that were reshared at least once by US-based adults (from July 1 2020 to February 1 2021). Only N ~ 12.1 million posts (1.2%) were reshared more than 100 times, involving N ~ 114 million adult U.S. users and accumulating ~ 55% of all views. We differentiate broadcasting versus peer-to-peer diffusion to show that: (1) Facebook is predominantly a broadcasting (rather than viral) medium of exposure; (2) Pages (not Groups) are the key engine for high-reach broadcasting; (3) misinformation (as identified by Meta's Third Party Fact Checkers) reverses these trends: this type of content relies on viral spread through long, narrow, and slower chains of resharing activity; and (4) a very small minority of users (older and more conservative) power the spread of misinformation, triggering very deep cascades that accumulate large numbers of views.

Authors

• Sandra Gonzalez-Bailon, University of Pennsylvania

• David Lazer, Northeastern University

• Pablo Barbera, Computational Social Science, Meta

• William Godel, New York University