Human performance in monitoring and controlling hierarchical large-scale systems

Human performance in monitoring and controlling activities in a hierarchical large-scale network, such as a communications system is considered. A scenario is described that is used in an experiment to examine three factors affecting humans functioning as network supervisors: cluster size (number of elements per display page), number of levels of pages in the hierarchy and failure rate per elements. The results indicate that increasing cluster size improves performance, increasing number of levels degrades performance, and failure rate affects only subjects' strategies.