The importance of item distinctiveness on performance using a menu selection system

Novice computer users searched an interactive menu system given either an explicit target phrase or a subject-matter topic. Two menus were used: an original menu as designed by a commercial timesharing service and a slightly modified version intended to increase the distinctiveness of same-level items. Subjects acquired knowledge about the system through one of four study methods: trial-and-error exploration, study of a diagram of the menu structure, trial-and-error exploration with documentation, or study of the diagram with documentation. Subjects using the modified menu (a) took less time per problem: lpar;b) found targets in a more direct path: and (c) gave up on fewer problems than subjects using the original menu. These results are consistent with a theory of choice that predicts that decision processes are facilitated by the distinctiveness of the alternatives. Overall the effect of study method was not significant. For highly meaningful menus, type of exposure, whether trial-and-error or study of the global tree, does not seem to matter.