As information systems continue to increase in complexity and power, they will become more difficult to learn and apply. The use of a single metaphor in interface design may not be sufficient for producing an appropriate mental model of any complex system since one metaphor can only represent a subset of a complicated system (Spiro, Feltovich, Coulson, & Anderson, 1989; Spiro, Vispoel, Schmitz, Samarapungavan, & Boerger, 1987). By incorporating multiple metaphors into a interface design, we may be able to create a more powerful representation of a complex system.
Only a few studies have paid attention to the insufficiency of using single metaphors and the power of using multiple metaphors in learning new concepts (Collins & Gentner, 1983, 1987; Gick & Holyoak, 1983; Rumelhart & Norman, 1981; Spiro, et al., 1987; 1989). In the studies of using multiple metaphors, discussions are held at the level of theory construction, with only a few systematic experimental results available. It is crucial that we examine the problems of using a single metaphor as well as investigate the use of multiple metaphors in interface design.
The purpose of this study is to: (a) examine the use of single metaphors and examine the limitations of single metaphors in interface design for complex systems; (b) discover the degree to which the strategy of incorporating multiple metaphors in interface design for complex systems facilitates learning of the complexity of the systems; and (c) investigate the role that training time plays in the learning process.