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CPS1834 Gumgum D. et al.
            in  rainfall  are  influenced  by  the  gravity  of  the  moon.  Based  on  Tsubatsa
            Kohyama's research, the authors consider the use of calendar based on the
            rotation of the moon compared to the rotation of the Sun.
                What  is  interesting  to  examine  from  the  problems  above  is,  whether
            rainfall data using the Hijri calendar will provide good results compared to
            rainfall  data  using  the  Gregorian  calendar  (AD).  If  the  extent  to  which  the
            difference occurs if both are modelled with the same model (SARIMA).

            2.  Method
                This research use Seasonal Model of ARIMA (autoregressive Integrated
            moving Average),the general ARIMA model can be write as follows;

                 M        K          i d     N
                          
                                         0 
                   j  ( ) (1 B   i s  ) =  +   k  ( )a
                               −
                       B
                                                   B
                                                       t
                 j= 1     i= 1               k  1 =
                Thus,  the  model  may  contain  K  differencing  factors,  M  autoregressive
            factors, and N moving average factors. This extension is useful in describing
            many non-standard time series that, for example, may contain a mixture of
            seasonal phenomena of different periods. Since it is this general form that
            most time series software use, we now explain this general model in more
            detail.
            The ith differencing factor is
                         i d
                  −
                (1 B  i s  )
            With the order si (the power B) and the degree di. If K=0, then  Z =  t  Z −  t   .

            Otherwise,   Z =  Z , as the mean of time series, does not exist. The parameter
                              t
                          t
              represents the deterministic trend and is considered only when  K  . The
                                                                                 0
              0
            jth autoregressive factor
                           −
                    B =
                                 −
                                          ... 
                                       2
                 j ( ) ( 1  1 j  B  2 j  B − −  jp j B  j p  )
            Contains one more autoregressive parameter,    jm  . The kth moving average
            factor is
                                       2
                 k  ( ) (1B =  −  k 1 B −  k 2 B − ... −  kq k B  k q  )
            And  contains  one  or  more  moving  average  parameter,    kn  .  In  most
            applications,  the  value  of  K,  M  and  N  are  usually  less  than  or  equal  to  2.
            Parameters  in  autoregressive  and  moving  average  factors  beyond  the  first
            factor of each kind are normally considered seasonal parameters in the model.
            The well-known Box Jenkins multiplicative seasonal ARIMA model
                                          D
                                 d
              P  ( ) ( )(1B   s  p  B  − B ) (1 B−  s ) Z =   q ( ) ( ) a Q  B s  t
                                                    B
                                             t
            Where

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