The implications of index-word selection strategies for user success in interactive searching were investigated in two experiments. People were asked to find target information objects using a simple interactive keyword information retrieval system in which the number of referent terms assigned to each object was systematically varied. The results demonstrate that searcher success is markedly improved by greatly increasing the number of names per object. © 1990 John Wiley & Sons, Inc.

Students performed a variety of tasks using a statistics text presented either in conventional printed form or via the text browser “SuperBook” (Remde, Gomez and Landauer [18]). Students using SuperBook answered more search questions correctly, wrote higher quality “open-book” essays, and recalled certain incidental information better than students using the conventional text. Subjective ratings overwhelmingly favored SuperBook. The advantage of SuperBook appears to be particularly strong for questions that are not anticipated by the author's organization of a text.

SuperBook is a hypertext browsing system designed to improve the usability of conventional documents. Successive versions of SuperBook were evaluated in a series of behavioral studies. Students searched for information in a statistics text. presented either in conventional printed form or in SuperBook form. The best version of SuperBook enabled students to answer search questions more quickly and accurately than they could with the conventional text. Students wrote higher quality “open-book” essays using SuperBook than they did with the conventional text, and their subjective ratings of the documentation strongly favored SuperBook. This work is a case study of formative design-evaluation. Behavioral evaluation of the first version of SuperBook showed how design factors and user strategies affected search and established baseline performance measures with printed text. The second version of SuperBook was implemented with the goal of improving search accuracy and speed. User strategies that had proved effective in the first study were made very easy and attractive to use. System response time for common operations was greatly improved. Behavioral evaluation of the new SuperBook demonstrated its superiority to printed text and suggested additional improvements that were incorporated into “MiteyBook,” a SuperBook implementation for PC-size screens. Search with MiteyBook proved to be approximately 25 percent faster and 25 percent more accurate than that obtained with a conventional printed book.