ABSTRACT
This chapter reviews current cognitive science research on how people understand visualizations of quantitative information. The chapter includes a description of cognitive models of visualization comprehension, including the contribution of perception, attention, working memory, and prior knowledge. Next, it provides demonstrations of how different visualizations of the same data sometimes convey different messages and how individuals with various levels of expertise and prior knowledge sometimes come up with different interpretations of the same display. These demonstrations are used to argue for principles of data-visualization design that have emerged from both theory and empirical studies, taking into account the fact that different displays can be more and less effective for different purposes and for different people. Finally, research on comprehension of test scores is reviewed in the light of cognitive science theories and empirical research, and implications are derived for the design of test scores for different stakeholders such as parents, teachers, and educational administrators.
