Studies in Plan Construction I: Analysis of an Extended Protocol

摘要

This report describes the analyses of long, thinking-aloud protocols collected from two expereinced software designers during their initial attempts at solving a moderately difficult design problem. Our method of analysis involves transforming the protocols into a series of rules in a condition-action format. These rules reflect the 'policies', or general strategies that guide design activities, 'goals', that indicate the actions that a designer intends to accomplish, and 'notes', that represent problem-specific information that was generated or retrieved during the course of problem solving. Solving a design problem involves the identification of the components that must be included in a design and the solutions of these components. The identified components represent the subproblems that must be solved in order to complete the design, and these solutions involve the creation and satisfaction of goals. In this report, we focus on the form and content of these goal structures and the manner in which they are generated. We conclude that the design components tend to be enumerated breadth-first on certain classes of design problems, and that the associated goals are explored depth-first. This cycle proceeds through multiple iterations and other processes constrain the expansions of these top-down processes. (Author)