Evaluation of HaloDot: Visualization of Relevance of Off-Screen Objects with over Cluttering Prevention on Mobile Devices

Abstract

The complexity of presenting and exploring large amounts of graphical data, on mobile devices, increases due to their small screen size. To mitigate this problem several approaches have been proposed to give clues about objects that are located off-screen. In this paper we present a user study comparing the Halo off-screen visualization technique with HaloDot, our approach that aims to improve direction awareness, as well as, relevance of offscreen objects, and to avoid cluttering of Halos. The study shows that searching and pointing relevant Points of Interest (PoI) can be achieved faster than with Halo and that the proposed aggregation method is useful.

Dynamic visualization of large numbers of off-screen objects on mobile devices

“…However, the distortion negatively affected distance estimation and user accuracy in locating off-screen objects. Another Halo variant, HaloDot [15], adds a small dot at the intersection between a circle and the intrusion border, i.e. the inner limit of the area where halos are visible, to improve direction awareness of off-screen objects.…”

Star Glyph Insets for Overview Preservation of Multivariate Data

“…The relevance of the aggregation is shown by thickness or transparency. Yet, different object classes are not considered [17]. Games and Joshi [15] carried on the concept of off-screen visualization and applied visual cues to statistical diagrams.…”

“…Then, along this line the object is mapped to the border region of the viewport. In addition, we adapt the idea of HaloDot [17], and use transparency as indicator for the distance between off-screen object and viewport, namely the relevance; objects located near to the viewport are considered to be of higher interest than objects located far apart. This is because it is likely that the user is interested in the surrounding of the area she is currently exploringonce she drills down from overview to detail.…”

Comparison of Off-screen Visualization Techniques with Representation of Relevance on Mobile Devices

“…By choosing between different interest functions, the user can control the visibility of the nodes. Although further studies are required, The HaloDot (Gonçalves et al 2011) consists on a variation of the Halo technique that includes the representation of the relevance. Like the Halo, this technique provides information about the location and the distance to the off-screen object based on the size and the curvature of the visible portion of the arc.…”

“…Therefore, transparency is used to emphasize the representation of the relevance (see Figure 3), i.e. the less relevant, the more transparent (Gonçalves et al 2011).…”