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CPS1832 Nur Fazliana Rahim et al.
                     The data was obtained from the Bank Negara Malaysia. In this part, the
                     dataset  of  Foreign  Exchange  Rate  (FER)  data  were  separated  into  two
                     subsets; FER-1 used for training and FER-2 used for testing. Each dataset
                     comprises 30 cases. The FER data includes three characteristic; One month
                     previous,  Two  months  previous  and  Three  months  previous.  There  are
                     three  classification  outcomes  of  the  FER  rank;  Small,  Intermediate  and
                     Large.
                  B.  Part 2: Creation of Fuzzy Rules
                         To generate the required fuzzy model using WSBA was introduced in
                     this phase. To create a system that is more readily understandable, WSBA
                     uses a rule generation algorithm based on fuzzy general rules or addition
                     of a Mamdani-type Fuzzy Rule Based Systems (FRBS). Five steps involve in
                     this part as follows.
                         First, three subgroups obtained from the training dataset based on the
                     classification  outcomes.    The  measure  of  location,   method  used  to
                                                                          
                     classify the outcomes as follows
                                                         − 
                                            =  + ( 4       )                      (1)
                                             
                                                  
                                                                  
                                                           
                     where    =  1, 2, 3,  =  cumulative  frequency  before  the    class,   =
                                        
                                                                                
                     total  number  of  observations,  =cumulative  frequency  before  the 
                                                                                           
                                                     
                     class,  =frequency of the class where   lies, and  = size of the class
                           
                                                             
                                                                         
                     where   lies.
                             
                         Second,  the  fuzzy  membership  function  for  FER  dataset  was
                     constructed  based  on  the  measure  of  location;  ,   and   calculated
                                                                      1
                                                                                 3
                                                                         2
                     respectively from equation (1). Then, the fuzzy partition was defined from
                     the established fuzzy membership function. It was used to convert crisp
                     values into fuzzy values.
                         Third,  for  each  linguistic  term,  fuzzy  subsethood  values  were
                     calculated  in  each  subgroup.  This  generated  rules  able  to  deal  with
                     classification  problems.  The  fuzzy  subsethood  value  of  A  taking  into
                     account , (, ) refers the degree levels to which A is subset of B [22],
                     [23]:





                      where (, )[0,1].
                  Fourth, using the subsethood values in Step 3, each linguistic term weights
                  then were obtained. In this research, weighting is restricted between 0 to 1,
                  which 0 is referring to the smallest weight (or less significance) and 1 the
                  largest weight (or more significance). The subsethood here is mean to extend

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