Cognitive support: designing aiding to supplement human knowledge

Abstract

This article advocates, as alternative for either the "classical" technology- or user-centred approach, to focus on the joint human-computer task performance in system design. Human involvement can be improved by designing system functions which complement human knowledge and capacities. Based on general needs for cognitive support, an aiding function is proposed which—in the process of task execution—takes the initiative to present context-specific, procedural task knowledge. Design of such aiding comprises two aspects: design of software and design of a human-computer system. Modern model-based software engineering methods provide strong support for the design of software systems, but little support for modelling the human-computer interaction. Current model-based methods are extended to address human-computer interaction issues. The resulting method comprises the design of easy-to-use-and-learn interfaces providing, if needed, aiding. In a case study, the method is applied to design a conventional plain interface and an aiding interface for the statistical program HOMALS. In an experiment, users with minor HOMALS expertise prove to perform their tasks better and to learn more with the aiding interface.