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CPS2222 Abdullah M.R. et al.
                      2.1 Radial Basis Function (RBF)
                      The Gaussian Radial Basis, is the commonly used type of kernel which is
                   given by
                                                                   2
                                                            ‖x − x ‖
                                                                  j
                                           K(x, x ) = exp [−        ]
                                                 j
                                                              2h 2

                      where  is the explanatory variable,   is the fractions of  and ℎ is the
                                                            
                   bandwidth kernel function. According to Rana et al. (2018), outliers can be
                   detected for only variables   by using cut-off-points as follows:
                                               

                                        CP RBF  = 2Med|Z | + 2√var(Med)
                                                        

                      where
                                                   =  ()

                      As this approach involves detecting all the outlier points by applying only
                   with one iteration, the computational cost would be less than those of the
                   conventional  techniques.  Additionally,  it  is  suitable  for  non-expert  users
                   because  it  introduces  fixed  set  of  parameters.  In  the  experimental  result
                   sections, the RBF kernel function is utilized with (ℎ = 1,   = 0,  = 10000),
                   using the predicted values to detect outliers.

                  3.  Nu- Support Vector Regression
                      Another class of  learning calculation, spurred by consequences by the
                  results  of  statistical  learning  theory  (Vapnik,  1995)  has  been  involved  by
                  Support Vector (SV) machines. They represent the decision boundary in terms
                  of a typically small subset (Schölkopf et aI., 1995) of all training examples,
                  called  the  Support  Vectors  which  is  initially  created  for  example
                  acknowledgment. Vapnik  devised the so-called ɛ −insensitive loss function,
                  according to (Deng et al, 2012) can be handle ε-SVR during a similar approach.
                   −SVR  is  changed  because  the  equivalent   −support  vector  regression
                  ( −SVR), wherever the parameter ε is replaced by a meaningful parameter .

                                           0                            | − ()| ≤ ,
                                  ( ) = { | − ()| −             
                                  
                                     
                                                               ℎ
                  which does not penalize errors below some   >  0, chosen a priori in order for
                  this property to carry over to the case of SV Regression (Schölkopf et al, 1999).
                  The primary issue of  −SVR based on (Chang et al, 2002) to Introducing the
                  corresponding  kernel  (,  ∗) = ((). ( ∗))  and  can  be  rewritten  as
                  follows
                                                                ℓ
                                              ‖‖ 2         1
                                                                        ∗
                                      +  ( + ∑( −  ))
                                                                    
                                               2             ℓ          
                                                               =1

                                        ((,  ) + ) −  ≤  + 
                                                                       
                                                               
                                                    
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