Information-Requirements Grammar: A Theory of the Structure of Competence for Interaction

In this paper, we argue that existing languages for representing routine cognitive tasks (such as GOMS, UAN, and PDL) can fail either because they demand that task competence is described using serial position to determine temporal order (and they are therefore overly restrictive) or because they demand that partial orderings are specified with temporal dependencies and other logical relationships (and they are therefore under-constrained). We propose a novel task description language, called Information-Requirements Grammar (IRG), which is motivated by a theory of how higher-level task performance is constrained by the information requirements and resource demands of lowerlevel tasks. We demonstrate the use of IRG and show how it replaces serial ordering and temporal dependencies with resource-bound information cascades between architectural information processes.