User perceptions and expectations of an information retrieval system

Performance measures are frequently used to evaluate user friendliness of a system. An equally important, but often overlooked factor is the users' attitudes towards a system. A prototype interface for information retrieval was developed for presenting engineering manuals online. It was tested on a representative sample of the intended end user community. We found that subjects' expectations were based on their experience with printed materials and other computer systems. Familiar search mechanisms (e.g., table of contents, index) were important for getting them started, even though they switched to other mechanisms as they gained more experience with the system. The fact that the index was more detailed than the one in the printed manual was seen by the subjects as critical for speedy and efficient information retrieval. Keyword search of the database was generally the preferred retrieval mechanism. However, some users preferred the index. The 'Table of Contents' which was a tree structured menu based system was found to be of limited use in the electronic medium, in contrast to the printed manual.