Self-selection of Information and Belief Update: An Experiment on COVID-19 Vaccine Information Acquisition

Rational information acquisition theory predicts that people select the more informative information. Thus, people's beliefs will be more persuaded by the information they select. We test the prediction in a critical real-world context -- information about COVID-19 vaccines. We conducted an online experiment in Taiwan where the subjects selected information about COVID-19 vaccines, and then the subjects updated their beliefs about vaccine effectiveness and references to vaccines. As our design distinguishes different stages of the rational acquisition framework, it allows us to diagnose the underlying mechanism of the theory. Our empirical findings demonstrate evidence that people's information acquisition generally coheres with the rational theory framework predictions; that is, people choose information when the information is more likely to alter their decisions. We show that our subjects' beliefs change more when they see the information they select. We also find evidence of change in vaccine preferences and choices after they receive the information they select, which further suggests that the subjects follow the rational information acquisition framework.