Honorable Mention

spEuler: Semantics-preserving Euler Diagrams

Rebecca Kehlbeck, Jochen Görtler, Yunhai Wang, Oliver Deussen

View presentation: 2021-10-29T14:00:00Z GMT-0600 Change your timezone on the schedule page
Exemplar figure, described by caption below
Venn diagrams are often used to highlight complex interactions of sets. This example fromxkcd.com shows which adjectives can be used in combination. Using our method, we can recreate the original Venn diagram. However, the diagram contains empty intersections. In these cases, Euler diagrams provide a more faithful representation of the data.

Creating comprehensible visualizations of highly overlapping set-typed data is a challenging task due to its complexity. To facilitate insights into set connectivity and to leverage semantic relations between intersections, we propose a fast two-step layout technique for Euler diagrams that are both well-matched and well-formed. Our method conforms to established form guidelines for Euler diagrams regarding semantics, aesthetics, and readability. First, we establish an initial ordering of the data, which we then use to incrementally create a planar, connected, and monotone dual graph representation. In the next step, the graph is transformed into a circular layout that maintains the semantics and yields simple Euler diagrams with smooth curves. When the data cannot be represented by simple diagrams, our algorithm always falls back to a solution that is not well-formed but still well-matched, whereas previous methods often fail to produce expected results. We show the usefulness of our method for visualizing set-typed data using examples from text analysis and infographics. Furthermore, we discuss the characteristics of our approach and evaluate our method against state-of-the-art methods.