A tale of two disasters: biases in risk communication

Abstract

Risk communication, where scientists inform policy-makers or the populace of the probability and magnitude of possible disasters, is essential to disaster management – enabling people to make better decisions regarding preventative steps, evacuations, etc. Psychological research, however, has identified multiple biases that can affect people’s interpretation of probabilities and thus risk. For example, availability (Tversky & Kahneman, 1973) is known to confound probability estimates while the descriptionexperience gap (D-E Gap) (Hertwig & Erev, 2009) shows low probability events being over-weighted when described and under-weighted when learnt from laboratory tasks. This paper examines how probability descriptions interact with real world experience of events. Responses from 294 participants across 8 conditions showed that people’s responses, given the same described probabilities and consequences, were altered by their familiarity with the disaster (bushfire vs earthquake) and its salience to them personally. The implications of this for risk communication are discussed.