A KEY FOR FRESH-WATER INVERTEBRATES USING FUZZY-LOGIC

Motivation: This paper summarizes a biological key using a fuzzy logic expert system. This approach allows the user to make some errors, be uncertain about some answers and not answer questions if unsure, but h ave an opportunity to identify unknown specimens correctly. This appro ach was adopted in order to develop a 'forgiving' key for users with l ittle or no prior knowledge of identification. The system was implemen ted using a multi-media expert system builder, 'Matcher', operating in a Microsoft Windows environment. Results: The paper reports the desig n issues for a key to identify freshwater invertebrates to family leve l and describes the types of questions used within the key, the fuzzy inference engine, the structure of the system and the methodology adop ted for testing it. Following this, an empirical test is reported of t he hypothesis that a fuzzy logic expert system can improve identificat ion accuracy for a sample of intended users. Finally, the discussion c onsiders the practicalities of using such a system as an aid to organi sm identification.