A tool for generating testable pop-out effects in geovisual displays
Keywords: pop-out, visual attention, geovisual analytics, evaluation
Abstract. The effectivity and efficiency of geovisual displays is highly dependent on visual search processes to detect, locate, and interpret relevant information for the tasks at hand. To speed up this process in interactive displays, a technique called “pop-out” is usually applied in order to afford visual prompts. By definition, such pop-outs depend on a sufficiently large contrast of the popped-out elements in regard to their contextual elements.
Visual attributes most suitable for attracting attention and hence potentially realising pop-outs are colour, motion, orientation, and size (Wolfe & Horowitz, 2004). Visual cognition theory suggests that items on a display featuring one of these visual attributes are processed pre-attentively, in parallel, and therefore need less time to be detected.
In previous work we proposed an approach to attention-guiding geovisualisation (Swienty, Reichenbacher, Reppermund, & Zihl, 2008). Based on visual cognition and design theory we demonstrated how relevant information can be visually encoded, such as to guide the users’ attention towards them. Although we collected first empirical evidence for the effectiveness of that approach, further and more detailed investigations are indispensable.
What we propose here is a tool for producing geovisual displays for empirical user studies. Such studies may test pop-outs, i.e. how contrast changes of display items make them faster detectable, and ultimately increase the effectiveness of such displays. The tool can also randomly select a set of target elements, i.e. those that should be emphasised and pop-out.