The media effect in Axelrod's model explained

TL;DR

This paper explains why introducing a fixed media influence in Axelrod's social model unexpectedly increases cultural diversity, revealing that local interactions tend to reduce diversity more than media-only interactions.

Contribution

The paper provides a simple explanation for the media effect in Axelrod's model, showing how local interactions influence cultural diversity.

Findings

Media-only interactions increase cultural diversity.

Local interactions reduce cultural diversity.

The model exhibits more diversity with media-only interactions.

Abstract

We revisit the problem of introducing an external global field -- the mass media -- in Axelrod's model of social dynamics, where in addition to their nearest neighbors, the agents can interact with a virtual neighbor whose cultural features are fixed from the outset. The finding that this apparently homogenizing field actually increases the cultural diversity has been considered a puzzle since the phenomenon was first reported more than a decade ago. Here we offer a simple explanation for it, which is based on the pedestrian observation that Axelrod's model exhibits more cultural diversity, i.e., more distinct cultural domains, when the agents are allowed to interact solely with the media field than when they can interact with their neighbors as well. In this perspective, it is the local homogenizing interactions that work towards making the absorbing configurations less fragmented as compared with the extreme situation in which the agents interact with the media only.