Selfish-rational non-vaccination: Experimental evidence from an interactive vaccination game

This paper provides an experimental game model - the Interactive Vaccination (I-Vax) Game - in order to investigate the behavioral consequences of risks from disease and from vaccination, and the epidemiological interdependence of vaccination decisions. Results from a controlled laboratory experiment provide evidence for selfish-rational non-vaccination: individuals react to the interactive incentive structure and make strategic vaccination decisions. We also find support for additional psychological factors determining behavior: individuals with stronger positive other-regarding preferences are more likely to vaccinate. Moreover, costs from action (vaccine-adverse events) have a stronger impact on behavior than costs from inaction (disease), which is evidence for the omission bias. Overall, we suggest that variants of the I-Vax Game can contribute to a better understanding of vaccination behavior and vaccine hesitancy. It can further be a useful experimental tool for testing interventions aiming at increasing vaccine uptake.