ABSTRACT
This chapter provides assurances that a goals, operators, methods, and selection rules for the methods (GOMS) description can be given for a display-oriented editor. A display-oriented editor may cause new issues to arise concerning the interaction of the user with the display. The chapter concens the accuracy of a GOMS model for predicting a user's action and shows how the GOMS model could be extended. Additional empirical studies would be necessary to validate the detailed predictions of the GOMS extensions. The chapter focuses on information-processing task analysis of text-editing by defining a symbolic representation for the instructions on the manuscript and by further explicating how these instructions lead to the behavior we observe. The purpose of a task analysis is to map out the constraints imposed on behavior by the nature and features of the task environment. The strict partitioning of the physical environment into independent processes that communicate through messages reflects the structure of the physical environment itself.
