Biased Information and Opinion Polarisation

Suen, Richard M. H. (2025): Biased Information and Opinion Polarisation.

Abstract

Why do people form polarised opinions after receiving the same information? Why does disagreement persist even when public information is abundant? We show that a Bayesian model with potentially biased public signals can answer these questions. When agents are uncertain and disagree about the bias in the signals, persistent disagreement and opinion polarisation can readily emerge. This happens because uncertainty surrounding the bias Induces agents with diverse initial beliefs to form drastically different posterior estimates. Prolonged exposure to these signals can in some cases drive the agents' opinions further away from each other and also further away from the truth.

• Item Type: MPRA Paper
• Language: English
• Keywords: Bayesian Learning, Biased Signals, Disagreement, Opinion Polarisation.
• Subjects: C - Mathematical and Quantitative Methods > C1 - Econometric and Statistical Methods and Methodology: General > C11 - Bayesian Analysis: General; D - Microeconomics > D8 - Information, Knowledge, and Uncertainty > D83 - Search ; Learning ; Information and Knowledge ; Communication ; Belief ; Unawareness

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