Computer interface evaluation using eye movements: methods and constructs

Eye movement-based analysis can enhance traditional performance, protocol, and walk-through evaluations of computer interfaces. Despite a substantial history of eye movement data collection in tasks, there is still a great need for an organized definition and evaluation of appropriate measures. Several measures based upon eye movement locations and scanpaths were evaluated here, to assess their validity for assessment of interface quality. Good and poor interfaces for a drawing tool selection program were developed by manipulating the grouping of tool icons. These were subsequently evaluated by a collection of 50 interface designers and typical users. Twelve subjects used the interfaces while their eye movements were collected. Compared with a randomly organized set of component buttons, well-organized functional grouping resulted in shorter scanpaths, covering smaller areas. The poorer interface resulted in more, but similar duration, fixations than the better interface. Whereas the poor interface produced less efficient search behavior, the layout of component representations did not influence their interpretability. Overall, data obtained from eye movements can significantly enhance the observation of users' strategies while using computer interfaces, which can subsequently improve the precision of computer interface evaluations. Relevance to industry The software development industry requires improved methods for the objective analysis and design of software interfaces. This study provides a foundation for using eye movement analysis as part of an objective evaluation tool for many phases of interface analysis. The present approach is instructional in its definition of eye movement-based measures, and is evaluative with respect to the utility of these measures. (C) 1998 Elsevier Science B.V, All rights reserved.