1. Introduction
In recent years the interest in data-driven approaches to the modeling of fuzzy system has increased. The key issue in constructing a fuzzy model is to identify the model structure. So far, the two widely used and particularly focused approaches are the self-organizing neural networks and fuzzy clustering [1]. However, these fuzzy modeling algorithms are difficult to determine the number of fuzzy rules systematically and effectively, so it is hard to balance the tradeoff between the necessary accuracy of the model and its complexity. Although there are some methods for rule base simplification about complexity reduction, but most of these methods tackle the problem from an interpretability view in order to obtain a transparent rule base [2]. Few researchers pay attention to the problem of generalization of fuzzy model, and how to get a good fuzzy model which gives excellent performance.