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Formulation of
                                             the
                Mathematical
                Mathematical  Formulation of  the  BME  Method        107
                                                 BME
                                                                      107
                                                       Method
        where
        where
            Z
               is the
                                     given
                                          by
                    partition
                             function
        and
        and  Z  is the  partition  function  given  by
            In view  of  Proposition  5.1, the  general knowledge equations  (Eq.  3.2)  are
        written  as follows



        Equation  5.9 is part  of the  basic BME  system of equations that we will develop
        below for  our spatiotemporal  mapping  purposes. The solution  of the system  of
        N c +  1 equations  (Eq.  5.9)  determines the  Lagrange multipliers  /j, a.

        C O M M E N T  5.2: Normalization   o f the pdf leads   t o th e following  expression





        for the  partition  function

         Then,    the   general knowledge  constraints   (Eq.   5.9)  are   also  written
         Then, the   general knowledge  constraints   (Eq.   5.9)  are   also  written   as as




        Hence,  th e functional  lo g Z ca n  b e viewed  a s  th e generator   o f  th e general




        knowledge equations.   The   solution   of   the   system   of   equations   (Eqs.   5.10


        and 5.11)   also   determines   the   Lagrange  multipliers  /j, a. Note   that   in   this



        system  th e Lagrange multiplier  ^o  ha s been   replaced  b y Z, an d  the number


        of constraint   equations  is N c; the   constraint for  a  = 0 has  been  replaced  by


        Equation 5.10.
        General   knowledge    in the  form  of  random field   statistics
        (including   multiple-point   statistics)
        As  we  saw  in  a  previous  chapter,  very  often  in  geostatistical  applications
        the  available  knowledge  has the  form  of  random  field  statistics  of  any  or-
        der  in  space/time.  In  the  language of  geostatistics,  the  latter  term  includes:
        space/time  moments  of  any order (1,..., A)  involving  up to  two  points  at a
        time; and space/time moments  involving more than two  points at a time—also
        called  multiple-point  statistics.
            This  sort  of  general  knowledge  is associated with  a distinct  class  of  9£-
        operators,  which  is  best  illustrated  by  means of  examples.  The  first example
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