A user-centred design and evaluation of IR interfaces.

This paper presents a user-centred design and evaluation methodology for ensuring the usability of IR interfaces. The methodology is based on sequentially performing: a competitive analysis, user task analysis, heuristic evaluation, formative evaluation and a summative comparative evaluation. These techniques are described, and their application to iteratively design a prototype IR interface, which was then evaluated, is described. After each round of testing, the prototype was modified as needed. The user- centred methodology had a major impact in improving the interface. Results from the summative comparative evaluation suggest that users' performance improved significantly in our prototype interface compared with a similar competitive system. They were also more satisfied with the prototype design. This methodology provides a starting point for techniques that let IR researchers and practitioners design better IR interfaces that are both easy to learn to use and remember. The paper concludes with some principles of interface design for IR systems. [ABSTRACT FROM AUTHOR]