How really effective are Multimodal Hints in enhancing Visual Target Spotting? Some evidence from a usability study

TL;DR

This study investigates the effectiveness of multimodal oral hints in aiding users to locate objects in visual displays, finding they significantly improve search performance especially in complex and radial layouts.

Contribution

It provides empirical evidence on how coarse spatial oral messages enhance visual target detection in different display structures and task difficulties.

Findings

Spatial hints improve search performance

More effective in radial layouts

Most useful for difficult tasks

Abstract

The main aim of the work presented here is to contribute to computer science advances in the multimodal usability area, in-as-much as it addresses one of the major issues relating to the generation of effective oral system messages: how to design messages which effectively help users to locate specific graphical objects in information visualisations? An experimental study was carried out to determine whether oral messages including coarse information on the locations of graphical objects on the current display may facilitate target detection tasks sufficiently for making it worth while to integrate such messages in GUIs. The display spatial layout varied in order to test the influence of visual presentation structure on the contribution of these messages to facilitating visual search on crowded displays. Finally, three levels of task difficulty were defined, based mainly on the target visual complexity and the number of distractors in the scene. The findings suggest that spatial information messages improve participants' visual search performances significantly; they are more appropriate to radial structures than to matrix, random and elleptic structures; and, they are particularly useful for performing difficult visual search tasks.