Opinion formation by belief propagation: A heuristic to identify low-credible sources of information

TL;DR

This paper introduces a belief propagation-inspired heuristic model for opinion formation that helps understand how individuals identify credible sources amidst noisy information networks, revealing a critical noise threshold affecting trust accuracy.

Contribution

The paper presents a realistic, cognitively affordable heuristic model for opinion formation based on belief propagation, analyzing its effectiveness under varying noise levels in information networks.

Findings

Existence of a critical noise level where source detection becomes impossible

Analytical and numerical validation of the model's behavior

Conditions under which opinions remain reliable despite noise

Abstract

With social media, the flow of uncertified information is constantly increasing, with the risk that more people will trust low-credible information sources. To design effective strategies against this phenomenon, it is of paramount importance to understand how people end up believing one source rather than another. To this end, we propose a realistic and cognitively affordable heuristic mechanism for opinion formation inspired by the well-known belief propagation algorithm. In our model, an individual observing a network of information sources must infer which of them are reliable and which are not. We study how the individual's ability to identify credible sources, and hence to form correct opinions, is affected by the noise in the system, intended as the amount of disorder in the relationships between the information sources in the network. We find numerically and analytically that there is a critical noise level above which it is impossible for the individual to detect the nature of the sources. Moreover, by comparing our opinion formation model with existing ones in the literature, we show under what conditions people's opinions can be reliable. Overall, our findings imply that the increasing complexity of the information environment is a catalyst for misinformation channels.