Effects of Functionally or Topographically Presented Process Schemes on Operator Performance

Abstract

Two presentation modes of process schemes were compared in a supervisory control task. Operators Monitored a submarine's trim system and had to identify process states and execute control orders. It was expected that the presentation of a functional arrangement would result in shorter identification times and fewer control errors than would a topographical arrangement. Results showed no differences between the two presentation modes with regard to the time required to identify a particular process state. The time needed to perform control settings was shortest in the functional presentation mode, but this effect decreased with practice. In both presentation modes, experienced subjects performed better than inexperienced subjects. The results were in line with expectations, except for a significant error increase with practice in the functional presentation mode. It is suggested that this effect is due to subjects relying increasingly on memory rather than on the presented information.