Coincident Visualization of Uncertainty and Value for Point Symbols

Abstract. The issue of uncertainty as a generic phenomenon in the natural world has been at the centre of both the cartographic and GI communities since the beginning of geographic data quality research. In accordance with the development of theoretical aspects of cartographic visualization and methods of uncertainty propagation in models, the generally accepted opinion is that uncertainty has to be presented to users in an unambiguous and understandable way. Despite reasonable amounts of work done in the field of uncertainty visualization methods (MacEachren1992, Leitner and Buttenfield 2000) and the testing of impact of visualization on decision making (Senaratne et al. 2012; Kinkeldy et al. 2015), there is still a wide gap between the uncertainty visualization theory and widely accepted use of uncertainty representation within decision making process. MacEachren et al. (2012), Fabrikant et al. (2010) initiated the discussion towards optimization of uncertainty visualization regarding visual semiotics and use of specific representations of uncertainty within complex mapping compositions and application context. However, their studies left also some open questions to be solved regarding the international audience of users.

The presented study focused on two unresolved topics, namely how would users perceive the uncertainty point map signs within a complex map field and what would be the appropriate visualization in case if there is a need to combine value and uncertainty together. Moreover, we performed the testing in two different cultural environments in Brno (Czech Republic, Europe) and Nanjing (China).