Abstract: Increasingly, the design of interactive computing systems appears to be a process of iterative design and re-design. One important factor in successful iterative design is iterative evaluation -- evaluation as part of each design cycle. This paper argues that different evaluation-design cycles may require different types of methodologies and different types of questions or measures to fully satisfy differing evaluation goals. Furthermore, evaluation procedures and measures themselves need to be designed and re-designed, a process more easily accomplished during system development. Examples based upon design projects illustrate some of the ways in which the nature and uses of evaluation procedures and information may change in different cycles of iterative evaluation.

Keywords: Analysis; Evaluation; Formative evaluation; Models and theories; Summative evaluation

Originally published: Proceedings of the Human Factors Society 33rd Annual Meeting, 1989, pp. 259-263

Republished: G. Perlman, G. K. Green, & M. S. Wogalter (Eds.) Human Factors Perspectives on Human-Computer Interaction: Selections from Proceedings of Human Factors and Ergonomics Society Annual Meetings, 1983-1994, Santa Monica, CA: HFES, 1995, pp. 167-171.