QOC Design Rationale Retrieval: A Cognitive Task Analysis and Design Implications
Simon Buckingham Shum · 1993
The study reported here addresses issues associated with the retrieval of semiformal, argu,mentation-based DR, taking the QOC notation as an example. If QOC-based DR is to be accessible, what requirements does this place on its representation? What are the cognitive tasks in retrieving relevant QOC in response to a query? How suited are graphical structures as a medium for QOC retrieval, and how do users manage multiple representations of a QOC when answering queries? Seven subjects answered queries about the design of two systems by formulating requests to an imaginary hypertext tool to display specific QOC information. Subjects had available to them -- for each system, in both textual and graphical forms, and at different levels of detail -- representations of the QOC, plus a hierarchical "Criterion tree" showing inter-Criterion relationships. The key results of this work were as follows: . A cognitive task model of the QOC retrieval process is developed as an analytic framework; . Errors in specifying QOC browsers are traced in the task model to different sources; . Multiple representations of the QOC are necessary to support different kinds of queries; tools could compute virtual structures to map relations between them; . Criterion trees which make inter-Criterion relationships explicit could be extended to compare the use of Criteria between different QOC DRs; . The general conclusion is that the coherence of a QOC's structure is critical to its reusability, but that this requirement is in tension with its semiformality; this is particularly the case with DR approaches which focus on representing the deliberation process , rather than the structure of its content.