Viral Misinformation: The Role of Homophily and Polarization

TL;DR

This paper investigates how homophily and polarization influence the spread of misinformation on social networks, revealing that shared beliefs and user clustering are key factors in viral false claims, rather than network hubs or influencers.

Contribution

It introduces an analysis of user behavior and network structure to identify the social factors driving misinformation virality, emphasizing polarization over traditional network influence metrics.

Findings

Homophily correlates with content consumption patterns.

Hubs and influencers are not primary drivers of misinformation spread.

Polarization and shared beliefs significantly impact virality.

Abstract

The spreading of unsubstantiated rumors on online social networks (OSN) either unintentionally or intentionally (e.g., for political reasons or even trolling) can have serious consequences such as in the recent case of rumors about Ebola causing disruption to health-care workers. Here we show that indicators aimed at quantifying information consumption patterns might provide important insights about the virality of false claims. In particular, we address the driving forces behind the popularity of contents by analyzing a sample of 1.2M Facebook Italian users consuming different (and opposite) types of information (science and conspiracy news). We show that users' engagement across different contents correlates with the number of friends having similar consumption patterns (homophily), indicating the area in the social network where certain types of contents are more likely to spread. Then, we test diffusion patterns on an external sample of $4,709$ intentional satirical false claims showing that neither the presence of hubs (structural properties) nor the most active users (influencers) are prevalent in viral phenomena. Instead, we found out that in an environment where misinformation is pervasive, users' aggregation around shared beliefs may make the usual exposure to conspiracy stories (polarization) a determinant for the virality of false information.