Bridging the Narrative Divide: Cross-Platform Discourse Networks in Fragmented Ecosystems

TL;DR

This paper introduces a platform-agnostic framework for reconstructing social graphs and tracking narrative spread across social media platforms, enabling better understanding of information dynamics in fragmented ecosystems.

Contribution

The authors develop a novel, platform-agnostic method that accurately reconstructs social networks and detects narratives across platforms, outperforming existing strategies with less data.

Findings

Identifies a small group of bridge users responsible for most narrative migration.

Reveals nearly 70% of migrating narratives originate from just 0.33% of users.

Demonstrates state-of-the-art performance in network tasks with less data.

Abstract

Political discourse has grown increasingly fragmented across different social platforms, making it challenging to trace how narratives spread and evolve within such a fragmented information ecosystem. Reconstructing social graphs and information diffusion networks is challenging, and available strategies typically depend on platform-specific features and behavioral signals which are often incompatible across systems and increasingly restricted. To address these challenges, we present a platform-agnostic framework that allows to accurately and efficiently reconstruct the underlying social graph of users' cross-platform interactions, based on discovering latent narratives and users' participation therein. Our method achieves state-of-the-art performance in key network-based tasks: information operation detection, ideological stance prediction, and cross-platform engagement prediction$\unicode{x2013}$$\unicode{x2013}$while requiring significantly less data than existing alternatives and capturing a broader set of users. When applied to cross-platform information dynamics between Truth Social and X (formerly Twitter), our framework reveals a small, mixed-platform group of $\textit{bridge users}$, comprising just 0.33% of users and 2.14% of posts, who introduce nearly 70% of $\textit{migrating narratives}$ to the receiving platform. These findings offer a structural lens for anticipating how narratives traverse fragmented information ecosystems, with implications for cross-platform governance, content moderation, and policy interventions.