GRAPHICAL ARGUMENTATION AND DESIGN COGNITION

Many efforts have been made to exploit the properties of graphical not ations to support argument construction and communication. In the cont ext of design rationale capture, we are interested in graphical argume ntation structures as cognitive tools to support individual and collab orative design in real time. This context of use requires a detailed u nderstanding of how a new representational structure integrates into t he cognitive and discursive flow of design, that is, whether it provid es supportive or intrusive structure. This article presents a use-orie nted analysis of a graphical argumentation notation known as QOC (Ques tions, Options, and Criteria). Through a series of empirical studies, we show that it provides most support when elaborating poorly understo od design spaces, but is a distraction when evaluating well-constraine d design spaces. This is explained in terms of the cognitive compatibi lity between argumentative reasoning and the demands of different mode s of designing. We then provide an account based on the collaborative affordances of QOC in group design meetings, and extend this to discus s the evolution of QOC argumentation from short term working memory to long term group memory.