Browse Theses

Knowledge acquisition has been recognized as a major bottleneck in building expert systems. Additional difficulties must be overcome when multiple experts provide the knowledge for a knowledge-based system. Although the group support system called Plexsys (now called GroupSystems) has been successfully used to elicit knowledge from multiple Help Desk experts to build the expert system known as ICE/H, additional investigation was required to determine to what extent the results obtained in building ICE/H could be generalized to other domains and to experts who are less comfortable with computers.

This research investigated the effectiveness of a group support system (GSS) in supporting knowledge acquisition from experts in corporate real estate disposition. All experts worked for different organizations. The six experts who contributed their knowledge met face-to-face for four knowledge acquisition sessions that were supported by Plexsys. At the end of every session, the experts evaluated the effectiveness of the GSS tools used to assist the group in reaching a consensus about the knowledge that an expert system for real estate disposition should contain. Successive versions of a knowledge-based system called DISPOSITION ADVISOR were developed after each knowledge acquisition session. The final version of the expert system prototype was evaluated by the experts who participated in the development of the program, other experts in corporate real estate disposition, real estate managers with some experience in disposition, and novices.

This research showed that the public screen can be a useful knowledge acquisition tool when the experts are not good typists, when the experts have not worked closely with one another and need to resolve differences in vocabulary, and when problems in the domain take a long time to solve. In the latter case, experts can identify missing information. Evaluation of DISPOSITION ADVISOR revealed that an expert system for disposition would be most useful if separate modules are offered for different types of properties, if the system allows the user to determine what features of the system he wants to use, if the system explains its reasoning, and if the system permits a record of the consultation to be saved and printed.