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CPS2174 Septian R. et al.
                  Therefore,  the  prediction  of  the  each  model  candidate  can  be  formulated
                  below.
                                             ̂ = ( );  = 1,2, … , 
                                                     ∗
                                             
                      Then, the averaging of the model candidate is
                                                        
                                                 ̂   = ∑   ̂
                                                             
                                                       =1
                      with   indicates the weight of -th model candidate, and ∑    = 1. [5]
                            
                                                                                    
                                                                               =1

                      2.3 Proposed Method
                      In  case  of  binary  response  variable,  ×1  = [ ];  ∈ {0,1},  the  model
                                                                    
                                                                         
                  candidate constructed by implementing the logistic regression to averaged in
                  model averaging process. The model candidate in this case can be described
                  below.
                                         ( ̂ ) = ( );  = 1,2, … , 
                                                        ∗
                                                

                      where  ∗ ×  contains  predictor variables that randomly selected from
                  . Then,  the  next  step  is  averaging  of  probability  prediction  each  model
                  candidates (  ) using the AIC weight,
                               
                                                       
                                                    = ∑  
                                                            
                                                      =1
                      before it transforms to be the class of response variable. In this research,
                  AIC weight applied to average the prediction each model candidates that is
                  based on the value of AIC in each model candidates. Suppose there are 
                  model candidates, therefore the  – th AIC weight follows
                                                          1
                                                      (  )
                                                             
                                               =        2  1
                                               
                                                   ∑    (  )
                                                               
                                                             2
                                                    =1
                      where   denotes the value of AIC in the  – th model candidates, and  ≥
                                                                                          
                             
                  0 ; ∑  =1  = 1 [6].
                           
                      In  practices,  the  data  set  separated  to  be  two  parts;  training  data  for
                  constructing the model, and testing data for evaluating the prediction. The
                  observation that selected to be the content of testing data selected randomly
                  with  size  about  40%  of  observations  that  is  100  observations,  therefore
                  training data has 187 observations. There are three  used in this research,
                   = {50,100,150} with  = 50 that to be evaluated by 100 replications in each
                  processes. In detail the randomly process for selecting observation in testing
                  data  and  for  selecting  predictor  in  model  candidate  are  applied  in  each
                  replictions.




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