The issue of how users can navigate their way through large information spaces is one that is crucial to the ever expanding and interlinking of computer systems. There are many ways of dealing with the issue of navigation one of which is to provide different dialogue styles to suit individual capabilities. The performance of users was compared on a menu style interface to a database system, which minimised navigation and constrained the dialogue, and a command style interface, which allowed an open and flexible dialogue. The results showed that some users did perform better on the interface which minimised navigational issues, and some better on the more open interface; and that users' performance related to their levels of spatial ability and experience with using command style interfaces. The menu interface proved suitable for users with both a low spatial ability and low experience of using command style interfaces. The command interface proved suitable for all users with a high spatial ability, whatever their previous experience, and for users with a low spatial ability but high experience of using command style interfaces. The results of this small scale experiment have potentially important ramifications for designers of interfaces to large information spaces.
AcknowledgementThis work formed part of a project entitled 'Adaptive Systems and User Modelling Tools', funded by the National Physical Laboratory, Teddington, UK, under extra-mural research agreement 82-0486. Francis Jennings conducted the experiments and wrote much of an earlier version of this paper.
