Diffusion Dynamics with Changing Network Composition

TL;DR

This paper investigates how changes in online communication network structures influence information diffusion during political mobilizations, revealing that increased hierarchy correlates with smaller information cascades and varies across user categories.

Contribution

It provides empirical analysis of network structural changes over time and their impact on diffusion dynamics during political protests.

Findings

Increased network hierarchy reduces cascade sizes.

Structural changes vary among user categories.

Network function in diffusion is more complex than theoretical models suggest.

Abstract

We analyze information diffusion using empirical data that tracks online communication around two instances of mass political mobilization, including the year that lapsed in-between the protests. We compare the global properties of the topological and dynamic networks through which communication took place as well as local changes in network composition. We show that changes in network structure underlie aggregated differences on how information diffused: an increase in network hierarchy is accompanied by a reduction in the average size of cascades. The increasing hierarchy affects not only the underlying communication topology but also the more dynamic structure of information exchange; the increase is especially noticeable amongst certain categories of nodes (or users). This suggests that the relationship between the structure of networks and their function in diffusing information is not as straightforward as some theoretical models of diffusion in networks imply.