Page 257 - Contributed Paper Session (CPS) - Volume 4
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CPS2219 Hasih P. et al.

                                                         
            Suppose that  +   (0)) =   =  , and   =  , thus equation (7) is
                                              
                                          ,
                                                              
                                                  
                                 
                                                          
            written as
                                 (| ) = exp( +  ( − ∑   ()))                          (8)
                                      
                                                    
                                                
                                                              
                                 
                                                           
            The parameter of the conditional intensity function in equation (8) is
            estimated using the maximum likelihood method with its likelihood function
                                                           2
                                = [∏ =1  (| )]exp (− ∫  (| )),                      (9)
                                               
                                          
                                                             
                                                                 
                                                          2
            and the Log-likelihood function
                                                            2
                               log  = ∑ =1 log  (| ) − ∫  (| ),                     (10)
                                                                  
                                                              
                                                    
                                                
                                                           2
            with time internal ( ,  ).
                                   2
                                1
               This section provides the application of conditional intensity function from
            the linked stress release model on earthquake data on Java and Bali-Nusa
            Tenggara. The earthquake data is secondary data sourced from the United
            States Geological  Survey.  Earthquake  data  includes  ,  , component  area
                                                                 
                                                                     
            ;  ,  with    states  that  the  time  of  the   -earthquake  and    states  the
                       
                                                                           
            magnitude of the -earthquake. The period of the earthquake data occurred
            from January 2010 to December 2017 with a magnitude of ≥5 mb and a depth
            of <70 km. Plot of time and magnitude of earthquake in Java and Bali-Nusa
            Tenggara is shown in Figure 1.
                              (a)                                     (b)
            Figure 1: Plot magnitude and time for earthquake data in Java (a) and Bali-Nusa Tenggara (b)
                Based on Figure 1 (a), there were three earthquakes in Java with the largest
            magnitude,  namely  in  the  south  of  Java  Island  on  3  April  2011  with  a
            magnitude of 6.5 mb, in the southeast of Adipala on 25 January 2014 with a
            magnitude of 6.1 mb, and in the northwest of Bunisari at 6 April 2016 with a
            magnitude of 6.1 mb. Based on Figure 1 (b), there were three earthquakes in






            Bali-Nusa Tenggara with the largest magnitude, namely in the Sumbawa on 8
            May  2010  with  a  magnitude  of  6.0  mb,  in  the  south  of  Bali  Island  on  13
            October 2011 with a magnitude of 6.1 mb, and in the west of Komerda on 12
            February 2016 with magnitude 6.3 mb.





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