Effects of flood risk visualization format on house purchasing decisions

We investigated how decision-making is affected by the visual presentation of flood hazard information. We exposed participants to different formats of flood hazard information while they simulated selecting a property to purchase. We compared three flood hazard formats: (i) maps currently used by the UK Environment Agency, (ii) tables that present flood level and frequency information and (iii) graphical representations depicting the level-frequency combination using a cartoon house image as a physical referent. In the experiment participants were presented, via computer screen, side-by-side information about two houses in a series of trials. Participants made a forced choice preference judgement between 108 different pairs of houses to indicate which they would purchase. Our findings indicate that when hazard information is presented in map format, individuals are less accurate in selecting lower-hazard houses, compared to when the same information is presented as a graphic representation of a house or as a table.