The effect of comparison cueing and exchange motion on comprehension of program visualizations

We describe an experiment that evaluates the effect of two attributes of an algorithm animation: presence of cueing (flashing) to indicate to the viewer that two data elements have been compared, and type of animation (arcing move or grow/shrink) to indicate that two data elements have exchanged values. We evaluate the impact of these attributes both on perception of the animated changes and on viewer comprehension of the depicted algorithm, as measured by the number of correctly answered questions in two question sets: "traditional" (comprehension) questions and "popup" (perception) questions. No significant effect on comprehension was observed for either flash cueing or exchange motion, though we note that comparison and exchange behaviors were redundantly cued in the animation studied. Signficant effects were found for flash cueing and "move" versus "grow" in the perceptual questions displayed in popup windows.