Tool Usage and Ecological Interface Design

Abstract

Field studies have shown that operators frequently use tools to “finish the design” of the interface, thereby overcoming design deficiencies. As far as we know, however, tool use has never been studied experimentally in the laboratory before in the cognitive engineering literature. In this paper, we describe an exploratory experiment that was conducted to address this issue. Two groups of participants controlled a thermal-hydraulic microworld with an ecological interface that contained physical and functional information in a single, integrated view. After an extended period of practice, each group was transferred to a different interface. One transfer interface contained the same information as the ecological interface, but across four screens that could only be viewed serially rather than in one integrated view. Another interface contained only physical information rather than physical and functional information. The results showed that tool use served four different purposes: to aid learning; to integrate information; to derive information; and to extend interface functionality. The results also provide indirect support for the ecological interface design framework because, in the transfer phase, tool use served to recover useful features that were present in the ecological interface.