Attention allocation within the abstraction hierarchy

Previous research has shown that Rasmussen’s abstraction hierarchy, which consists of both physical and functional system models, provides a useful basis for interface design for complex human—machine systems. However, very few studies have quantitatively analysed how people allocate their attention across levels of abstraction. This experiment investigated the relationship between attention allocation strategies and performance on a thermal-hydraulic process simulation. Subjects controlled the process during both normal and fault situations for about an hour per weekday for approximately one month. All subjects used a multi-level interface consisting of four separate windows, each representing a level of the abstraction hierarchy. Subjects who made more frequent use of functional levels of information exhibited more accurate system control under normal conditions, and more accurate diagnosis performance under fault trials. Moreover, subjects who made efficient use of functional information exhibited faster fault compensation times. In contrast, subjects who made infrequent or inefficient use of functional information exhibited poorer performance on both normal and fault trials. These results provide some initial, specific evidence of the advantages of an abstraction hierarchy interface over more traditional interfaces that emphasize physical rather than functional information. ( 1998 Academic Press Limited