On Rule Induction Method Based Rough Sets in Diagnostic Expert System

It usually takes a long period to acquire plant disease knowledge using the traditional methods during the development of expert system. This paper describes relations between rough set theory and rule-based description of plant diseases, which corresponds to the process of knowledge acquisition of expert system. Then the exclusive rules, inclusive rules and disease images of rape-seed disease are built based on the PDES diagnosis model, and the definition of probability rule is put forward. At last, the paper presents the rule-based automated induction reasoning method, including exhaustive search, post-processing procedure, estimation for statistic test and the bootstrap and resampling methods. We also introduce automated induction of the rule-based description, which is used in our plant diseases diagnostic expert system. The experimental results show that rough set theory gives a very suitable framework to represent processes of uncertain knowledge extraction