Modeling cross-platform narrative diffusion: a stable Hawkes–ODE framework for exposure and adoption dynamics
摘要
Understanding how narratives spread across social media platforms requires a framework that captures both the stochastic generation of posts and the gradual evolution of user engagement. This study proposes a cross-platform diffusion model that integrates a marked multivariate Hawkes process with a bounded exposure–adoption ordinary differential equation (ODE). The Hawkes component models event arrivals and cross-platform excitation, while the ODE captures how exposure translates into active engagement over time. Applied to the 2025 U.S. tariff-war discourse spanning 30,493 Instagram, 11,218 TikTok, 12,252 X, and 30,493 YouTube posts collected between January and May 2025, the model reveals interpretable and stable cross-platform influence dynamics. The estimated branching matrix (