Transient Behavior of Gossip Opinion Dynamics with Community Structure

TL;DR

This paper analyzes the early-stage transient behavior of gossip opinion dynamics in networks with community structure, revealing phase transitions influenced by intra- and inter-community weights and stubborn agents, supported by theoretical bounds and numerical validation.

Contribution

It provides the first theoretical bounds on transient opinion behavior considering community structure and stubborn influence, highlighting phase transitions in early opinion formation.

Findings

Large intra-community weights lead to community-specific opinion clustering.

Small differences between intra- and inter-community weights result in consensus around the global average.

Strong stubborn influence causes opinions to quickly stabilize to steady states.

Abstract

We study transient behavior of gossip opinion dynamics, in which agents randomly interact pairwise over a weighted graph with two communities. Edges within a community have identical weights different from edge weights between communities. We first derive an upper bound for the second moment of agent opinions. Using this bound, we obtain upper bounds for probability that a large proportion of agents have opinions close to average ones. The results imply a phase transition of transient behavior of the process: When edge weights within communities are larger than those between communities and those between regular and stubborn agents, most agents in the same community hold opinions close to the average opinion of that community with large probability, at an early stage of the process. However, if the difference between intra- and inter-community weights is small, most of the agents instead hold opinions close to everyone's average opinion at the early stage. In contrast, when the influence of stubborn agents is large, agent opinions settle quickly to steady state. We then conduct numerical experiments to validate the theoretical results. Different from traditional asymptotic analysis in most opinion dynamics literature, the paper characterizes the influences of stubborn agents and community structure on the initial phase of the opinion evolution.