Methods of Content Specification

Cognitive engineers commonly use either system-based or task-based analysis methods to identify information content requirements for system design. However, relatively little is known about the relationship between these two classes of methods. This article provides a comparison of the requirements generated by one system-based analysis and two task-analyses in designing an interface for a complex production process. A comparison of the requirements identified by each analysis revealed that, while there was a substantial overlap between them, the two classes of methods produced largely complementary information. Further analysis revealed that the existing instrumentation system in the plant was not sufficient to support many of the content requirements, and that this limited the effectiveness of the existing interface. These findings yield important implications for the design of complex human-machine systems