What defines the success of maps and additional information on a multi-hazard platform?

Triggered by technical progress that has allowed for the combining of information about natural, anthropogenic and socionatural hazards, numerous multi-hazard platforms have been established over the last years. Despite their increasing use, surprisingly, little research has been conducted evaluating how the public perceives of the hazard information provided by these multi-hazard platforms. Because most of them use maps on the start page, we were especially interested in the different approaches towards presenting multiple hazards and towards compiling the contents of the hazard announcements attached to the maps. With an online conjoint choice experiment (N = 768, fully randomised design), we tested different start page designs and hazard announcements representing the diversity of elements used in multi-hazard platforms. The alternatives were randomly displayed as pairs to the participants (between-subjects design), asking them to first rate the alternatives separately and then to choose which of the two they preferred. Our main results are that the participants prefer a start page consisting of a single map with textual information about the current hazards below the map. In addition, they prefer hazard classifications with four or five hazard categories. Moreover, the participants appreciate the embedding of a sharing function in the hazard announcements. Finally, the participants prefer a combination of textual and pictured behavioural recommendations. To conclude, the results indicate that the design of information provided on multi-hazard platforms indeed affects the public's preferences. Therefore, in parallel to the continuous improvement of scientific-technical products, the communication and perception of these products should be systematically examined too.