OA-graphs: orientation agnostic graphs for improving the legibility of charts on horizontal displays

Horizontal displays are emerging as a standard platform for engaging participants in collaborative tasks. Little is known about how groups of people view visualizations in these collaborative settings. Several techniques have been proposed to assist, such as duplicating or reorienting the visual displays. However, when visualizations compete for pixels on the display, prior solutions do not work effectively. We first ran an experiment to identify whether orientation on horizontal displays impacts the legibility of simple visualizations such as charts. The results reveal that users are best at reading a chart when it is the right side up, taking them 20% less time to read than when it is upside down. This insight led us to develop the Orientation Agnostic Graph (OA-Graph), making use of a radial layout designed to be legible regardless of orientation. In a second experiment we found that users can read OA-Graphs better than when the graphs are upside down but less well than traditional graphs in the right side up. The design of our novel visualization, informed by radial visualization methods will assist designers in developing charts that are not easily affected by user orientation, an issue that is prevalent in collaborative table-top systems. Certain tasks such as observing relative differences can benefit from OA-Graphs.