Proceedings of the Annual Meeting of the Cognitive Science Society

Communicating uncertainty to lay audiences is as challenging as indispensible if people are to understand medicaltest results, gains from financial investments, or weather warnings.Compared to risk communication in the medical domain, there is so far only limited evidence on how to best communicateuncertainty for continuous quantities, such as financial returns or wind speeds (Spiegelhalter et al., 2011).The poster presents results from a longitudinal study investigating this question within a real-life setting. We implementeddifferent representations communicating probabilistic weather forecasts within an online information system operated by theGerman National Weather Service. The system is used by fire brigade coordination centers throughout Germany to prepare forsevere weather conditions.By analyzing web usage and search behavior, we investigate which representations users rely upon under real operationalconstraints. We link the analysis to tests which representations are best understood and could thus aid emergency managers intheir decisions.