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Fuzzy approaches have become one of the well-known solutions for the classification problems due to their powerful capabilities to handle both imprecision and uncertainty concepts. The generation of membership function and the generation of the associate fuzzy rules constitute the key tasks in the design of fuzzy systems. For this purpose, a large variety of methods have been introduced. This includes: heuristic methods (Abe & Lan, 1995; Nozaki et al., 1997; Viattchenin et al., 2013), Genetic Algorithms (GA) (Antonelli et al., 2014;Cordon et al., 1998; Mansoori et al., 2008; Yuan & Zhuang, 1996), Artificial Immune Systems (AIS) (Alves et al., 2004; Lei & Ren-hou, 2008), Ant Colony Optimization (ACO) (Ganji & Abadeh, 2011; Saniee et al., 2008), Particle Swarm Optimization (PSO) (Chen, 2006; Ganeshkumar et al., 2013; Kashanipour et al., 2008; Permana & Hashim, 2010), Neural Networks (Chen et al., 1995; Nemissi et al., 2014; Pranevicius et al., 2014), and clustering methods (Chen et al., 2011; Jamsandekar & Mudholkar, 2013; Jamsandekar & Mudholkar, 2014; Kahali et al., 2017; Mahata et al., 2018).
The advantage of clustering based-approaches, in which every rule corresponds to one cluster, lies in the fact that they permit generating efficient classifiers with few rules. Indeed, in grid-partitions methods, the feature space is divided into all possible regions and each of them is represented by one fuzzy rule. This process generates a large number of rules, especially in high-dimensional problems where the number of rules becomes exponentially huge (curse of dimensionality). These rules have to be then selected and tuned. Furthermore, in clustering based-approaches the parameters of the membership functions, i.e. centers and width, can be automatically set by projecting the obtained clusters.