Page 266 - Modern Spatiotemporal Geostatistics
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Popular  Methods  in  the  Light  of  Modern  Geostatistics  247





























                                            2
        Figure  12.13.  Data  configuration  in  R .  Measurements (hard  data)  are
              available  at  points  indicated  by  V;  soft  data  are available at  points
              indicated  by open circles.  The  estimation  point  is indicated  by  x.

        and (ii.)  the  Gaussian  model



        both  with  a  =  1.  At  three  points  that  are  kept  fixed  for  all  simulations
        only  (soft)  interval  data  are  provided.  We  assume  that  there  are  13  inter-
        vals  [otj,  otj+\}.  The  limits of  these intervals are the  threshold  values that are
        considered  in  IK.  The  intervals  are defined as follows







                 1
        where F x (p)  is the  p-quantile  of  the  standard Gaussian  law.  Each  point  is
                                              a
                                           a
        randomly  assigned an interval  x(Pi)  e  ( j> j+i]-  Estimates  Xk  are sought
        at  the  point  p k—the  same  for  all  simulations.  The  ten  points  with  known
        process  values constitute the  hard data  points,  while  the  three  locations with
        interval  data are the  soft  data  points.  In order to  avoid  methodological  issues,
        we  assume that  all  parameters of  the  multivariate  Gaussian  law are known  in
        advance  for  both  BME  and  IK.  For the  same reason, the  same  intervals  have
        been  chosen for  all  points.  BME  does  not  require that  the  same  intervals  be
        used  for  all  points.  Since we assume that  complete  knowledge  about  the  dis-
        tribution  is available,  we can  use simple  IK  to  compute  the  probabilities  and
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