Page 230 - Modern Spatiotemporal Geostatistics
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Single-Point  Analytical  Formulations          211































         Figure  10.7.  CPU time  (sec) of  BME  estimation  on an HP-9000/C160  work-
              station.


             Naturally, as improvements are made in the computer  programming  of  the
         BME techniques, the complexity of the numerical  algorithms and the  associated
        computational  costs will continue to  decrease.

         Generalized     Covariance—Hard           and   Soft  Data

         Readers unfamiliar with the S/TRF-i//^ theory  (Christakos,  1991b,  1992) may
        skip  this  section.  We will  start  by  proving  a fundamental  proposition,  which
        deals with situations  in which the spatiotemporal  pattern of the natural variable
         under  consideration  is characterized  by spatially nonhomogeneous and  tempo-
         rally  nonstationary variations.
         PROPOSITION    10.4:  The  specificatory  knowledge  is  as  described  in
         Proposition  10.1.  The  general  knowledge  consists of  the  generalized
        spatiotemporal  covariance  of  orders v/n  between  any  pair  of  points  in
        Pmap = {Pi\ * = !,-•• m, k}. Then, the BME posterior pdf is given by
         Equation  6.17  (p.  132)  with




        and
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