Three experiments were undertaken to investigate drivers' responses to displayed speed information. In the first, subjects were shown images of different designs of speedometers. These speedometers were manipulated in terms of their type of display, level of complexity and speed displayed. The subjects' task involved reading numerical information and responding as quickly as possible to whether the value shown on the speedometer was under or over 40 miles per hour. The second experiment used the same stimuli. The task for subjects, however, was to detect changes in the displayed speed by paying attention to two consecutively presented speedometers and making a decision according to if the second speedometer displayed a faster or a slower speed than the first one. The aim of Experiment III was to explain the incongruent results found between the first experiment (where the digital display produced the best results) and the second experiment (where the digital types performed worst). Both experimental tasks are crucial when driving, therefore were combined in this experiment. The results found that when both tasks were performed sequentially, the digital speedometers produced slower reaction times compared with the analogue ones for the reading numerical information task but for the detecting change task the type of display does not affect performance. Similarly, the digital speedometers were responded to the least accurately when compared with the analogue versions. In addition, the subjects performed better in the detecting change task than in the 'Under or over 40 mph' task - both in terms of quick reaction times and accurate responses. Finally, the speedometers with a medium level of complexity were responded to quicker and more accurately than were those with high complexity. For the covering abstract see ITRD E113725 (C 22328 CD-ROM).
Samenvatting