HUMAN FACTORS, 1985,27(2),157-162 Minimizing User Search Time in Menu Retrieval Systems

The optimal structuring of menu indexes in computerized information retrieval is examined. The number of alternatives per page that minimizes search time is determined as a function of the human and machine factors of search strategy, scanning time, key-press time, and computer response time. For a wide range of conditions, the optimal number of alternatives per page is in the range of from four to eight, with limiting integer values of three and four for exhaustive and self-terminating search, respectively. The spread of computers in recent years has been stimulated in part by an increased demand for information-retrieval services. A case in point is the recent development of vid-eotex systems (Pres tel in Britain, Antiope in France, and Telidon in Canada). Videotex is an interactive system designed to present tex-tual and graphic information at the com-mand of the user (Madden, 1979; Tydeman, Lipinski, Adler, Nyhan, and Zwimpfer, 1982). The user typically employs a keypad or key-board and a computer terminal to interact with a central computer via telephone lines or two-way cable. Coincident with the development of inter-active computer systems has been the wide-spread adoption of a relatively new method of retrieving information, known as th