Date of Award


Document Type

Campus Access Thesis



First Advisor

Sarah Battersby


People seeking information to guide their learning, understanding, and decision-making frequently come into contact with data of varying degrees of reliability. This is unavoidable as uncertainty is inherent in information.

While the literature acknowledges the importance of communicating uncertainty through visualization, there is little agreement regarding best practices. A review of the geographic literature was conducted to learn about current work relating to uncertainty visualization. This review found many proposed ideas for how to visually represent uncertainty, but not many conclusions about which methods worked best. In order to address this need, fourteen sets of point symbols have been designed that aim to communicate a data value as well as its corresponding degree of reliability. These symbols were developed based upon ideas posed in the cartographic literature.

Two separate studies were conducted to evaluate the overall performance of the designed symbols through surveys. The first study was a comprehensive evaluation of the intuitive communicative abilities of the fourteen proposed symbol strategies. The six highest performing symbols were then tested in a second study which placed these symbols on maps in a decision support system environment. This research generated comprehensive empirical findings that indicate effective symbolization strategies for communicating information and its underlying uncertainty on maps. This paper reports these findings.