How Availability Heuristic, Confirmation Bias and Fear May Drive Societal Polarisation: An Opinion Dynamics Simulation of the Case of COVID-19 Vaccination

The stark contrast between different opinions on COVID-19 vaccination suggests that the underlying opinion dynamics is a topic worth studying. Here we build a comprehensive agent-based model by incorpo-rating fear into the HUMAT framework to study how the availability heuristic and confirmation bias influence information processing and impact the opinion dynamics and vaccination rate in the case of the COVID-19 pan-demic. Three scenarios are designed to explore the impact of the disease severity, confirmation bias, and au-thorities on COVID-vaccination opinion polarisation and the vaccination rate. Main simulation results indicate that: 1) Increased fear of disease raises the vaccination rate and accelerates people's uptake of COVID vaccines. 2) Confirmation bias fuels opinion polarisation through the mechanism of information selection and improves the satisfaction of different groups. 3) Opposing authorities and availability heuristic promote opinion polarisa-tion, while more moderate authorities reduce polarisation but do not make it disappear. Implications of these results are discussed for science communication related to complex societal problems.