Out of the Plane: Flower versus Star Glyphs to Support High-Dimensional Exploration in Two-Dimensional Embeddings

Abstract

Exploring high-dimensional data is a common task in many scientific disciplines. To address this task, two-dimensional embeddings, such as tSNE and UMAP, are widely used. While these determine the 2D position of data items, effectively encoding the first two dimensions, suitable visual encodings can be employed to communicate higher-dimensional features. To investigate such encodings, we have evaluated two commonly used glyph types, namely flower glyphs and star glyphs. To evaluate their capabilities for communicating higher-dimensional features in two-dimensional embeddings, we ran a large set of crowd-sourced user studies using real-world data obtained from data.gov. During these studies, participants completed a broad set of relevant tasks derived from related research. This paper describes the evaluated glyph designs, details our tasks, and the quantitative study setup before discussing the results. Finally, we will present insights and provide guidance on the choice of glyph encodings when exploring high-dimensional data.

Active Gaze Labeling: Visualization for Trust Building

“…We represent the gaze thumbnails as circles, resembling the foveated area the eye was focusing on. From the selection of radial representations such as sunbursts, radar charts, star glyphs, or similar information visualization techniques, we decided to adapt the concept of flower glyphs for their suitability for pattern detection [10]. This glyph design serves as a metaphor, putting the annotator in the role of a plant taxonomist, searching for flowers not seen before and labeling them accordingly.…”

“…In this vein, we propose a visualization-based approach to identify and label fixations in eye tracking videos. A glyph representation of individual fixations, the EyeFlower (see Figure 1), shows a thumbnail image of the respective fixation and provides information on class predictions with an extension of a flower glyph [10] where petals represent individual AOIs. Glyphs can be selected and annotated with a respective AOI label.…”