Effective Uncertainty Visualization for Aftershock Forecast Maps

• Activity Number: 88 - Data Visualization in Practice
• Type: Contributed
• Date/Time: Monday, August 9, 2021 : 10:00 AM to 11:50 AM
• Sponsor: Section on Statistical Graphics
• Author(s): Max Schneider* and Michelle McDowell and Peter Guttorp and E. Ashley Steel and Nadine Fleischhut
• Companies: University of Washington and Harding Center for Risk Literacy and University of Washington and Norwegian Computing Center and United Nations Food and Agriculture Organization and Max Planck Institute for Human Development
• Keywords: uncertainty visualization; uncertainty communication; spatial uncertainty; earthquakes; natural hazards; data visualization

Abstract

Research on uncertainty visualization (UV) is missing from earthquake science. We present a pre-registered online experiment to test the effectiveness of three UV techniques for displaying aftershock forecasts. These maps show the expected number of aftershocks, and its uncertainty, at each location for a week following a hypothetical mainshock. Three UVs are considered: (1) forecast and uncertainty maps adjacent to one another; (2) the forecast map depicted in a color scheme, with the uncertainty shown by the transparency of the color; (3) two maps that show the lower and upper bound of the forecast distribution at each location. Subjects complete two map-reading tasks that target different dimensions of the readability of the UV. They then perform a comparative prediction task, which demonstrates whether a UV is successful in reaching two key communication goals. All UVs perform equally well in the goal of communicating “sure bet’’ situations. But the UV with lower and upper bounds is significantly better than the other UVs at communicating “potential surprises.” We discuss the implications of these results for better uncertainty communication for spatial forecasts.