Abstract
Fuzzy modeling based on fuzzy ID3 has been used for its efficiency in selecting input variables. One of major difficulties of fuzzy ID3 is that it is difficult to determine the fuzzy partition in case human's sufficient knowledge about the partition is not available. Against this difficulty, a method for fuzzy partition based on information contained in data was proposed. This method, utilizes the shape of expected value of information, and does not need veteran's experience. However the degree of freedom in deciding the membership functions for the fuzzy partition is high, and the method shows only a guideline for the decision. This paper presents a method for determining the membership functions for fuzzy ID3 based on smoothing of acquired information. The membership functions are to be used for a fuzzy model. This method utilizes the unique feature of fuzzy technology that is smoothing of data and interpolation of inferred values of rules. The proposed method is applied to identification of predictor of oxygen component of an oil refinery plant.