The Effects of Manipulating Recognition Variables on the Transition from Menus to Commands

The needs of users vary along with their degree of acquired expertise, with novices gladly accepting much-needed guidance and experts preferring to use the knowledge that they have gained with repeated use. The study of human-computer interaction recognizes this difference, and numerous interaction strategies have been developed to accommodate expertise differences. One such strategy is that of transitional interaction. This strategy accommodates the users' need to move up and down the scale of expertise by allowing them to toggle between recognition and recall modes. The goal of this research is to study in more detail the impact of manipulating recognition mode variables and their effect on inexperienced users' transitions from menu to command interaction. Two experiments were designed and conducted to meet the above stated goal. The first experiment compared the effects of supporting a recognition mode versus command interaction only. Specifically, a transitional interface to UNIX was compared with a shell-based UNIX interface on measures of user performance and perceived usability. The transitional version resulted in both higher performance and higher perceived usability. The second experiment investigated the effects of menu item selection strategy on the transition from menu to command. The strategy of command completion to a unique form proved superior to typing a paired number as measured by trials to complete and accurate recall