The Role of the Magnitude of Change in Detecting Fixed Enumeration Units on Dynamic Choropleth Maps

Dynamic maps are commonly used for the depiction of quantitative information. However, their users often fail to notice changes in the intensity of geographic phenomena. Moreover, if the distribution of colour values between two scenes changes, the user might have a problem with recalling the colour arrangement from the previous scene. A commonly occurring mistake is indicating that the colour changed its value, while in reality it did not. This paper examines the potential impact of the magnitude of change on the detection of the fixed enumeration units of a dynamic choropleth map. The research is based on Signal Detection Theory methodology and uses eye-tracking technology to examine the change blindness phenomenon on spatiotemporal maps. The results show that regardless of the magnitude of change and the number of enumeration units, the participants were convinced that the colour value in a particular place changed, even though it did not.