Designing with Pictographs

A set of 8 infographics in two rows. Each row of charts appear identical in layout, text, and color, except the top row uses small symbols in place of the more traditional blocky shapes of the lower charts. — How do infographics with pictograph arrays influence understanding when compared to those that use geometric areas? The figure above displays 4 of the 6 pairs of charts evaluated in this study. Each pair consists of a chart using a pictograph array to encode a part-to-whole relationship (upper row) and a chart using a geometric area to encode the same information (lower row).

Led by: Alyx Burns

Past studies have shown that when a visualization uses pictographs to encode data, they have a positive effect on memory, engagement, and assessment of risk. However, little is known about how pictographs affect one’s ability to understand a visualization, beyond memory for values and trends. We conducted two crowdsourced experiments to compare the effectiveness of using pictographs when showing part-to-whole relationships. In Experiment 1, we compared pictograph arrays to more traditional bar and pie charts. We tested participants’ ability to generate high-level insights following Bloom’s taxonomy of educational objectives via 6 free-response questions. We found that accuracy for extracting information and generating insights did not differ overall between the two versions. To explore the motivating differences between the designs, we conducted a second experiment where participants compared charts containing pictograph arrays to more traditional charts on 5 metrics and explained their reasoning. We found that some participants preferred the way that pictographs allowed them to envision the topic more easily, while others preferred traditional bar and pie charts because they seem less cluttered and faster to read. These results suggest that, at least in simple visualizations depicting part-to-whole relationships, the choice of using pictographs has little influence on sensemaking and insight extraction. When deciding whether to use pictograph arrays, designers should consider visual appeal, perceived comprehension time, ease of envisioning the topic, and clutteredness.

If you are interested in working on or learning more about this project, please contact Alyx Burns at alyxanderbur@cs.umass.edu