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Concerning the  flexibility of  PR  design  software, there  is a broad  spectrum of
    possibilities.  At  one  end  we  find  "closed"  products  where  the  user  can  only
    perform  menu  operations. At  the other end  we  find  "open" products  allowing the
    user to program  any arbitrarily complex PR algorithm. A popular example of such
    a product is Marlab  from The Marh Works, Inc., a mathematical  software product.
    Designing  a  PR  application  in  Marlab  gives  the  user  the  complete  freedom  to
    implement  specific algorithms and  perform complex operations, namely  using  the
    routines  available in  the Marlab Toolboxes. For instance, one can  couple routines
    from  the  Neural  Networks  Toolbox  with  routines  from  the  Image  Processing
    Toolbox  in  order  to  develop image  classification  applications. The  penalty  to  be
     paid  for  this  flexibility  is  that  the  user  must  learn  to  program  in  the  Matlab
     language, with non-trivial language learning and algorithm development times.
       Some  statistical  software  packages  incorporate  relevant  tools  for  PR  design.
     Given  their  importance  and wide  popularisation  two  of  these  products  are worth
     mentioning:  SPSS from SPSS Inc.  and  Siatistica from StatSoft Inc.  Both  products
     require  minimal  time  for  familiarization  and  allow  the  user  to  easily  perform
     classification  and  regression  tasks  using  a  scroll-sheet  based  philosophy  for
     operating with  the data. Figure  1.14 illustrates the Statistics scroll-sheet  for a cork
     stoppers classification  problem  with  colunln C filled  in  with  numeric codes of the
     supervised class labels and the other columns (ART to  PRT) filled in  with  feature
     values.  Concerning  flexibility,  both  SPSS  and  Siaristica  provide  macro
     constructions.  As a matter of  fact Siatistico is somewhere between  a "closed" type
     prnduc~ and  Matlab, since it  provides  programn~ing facilities  such  as  the  use  of
     external code (DLLs) and  application programming  interfaces (API). In this book
     we  will  extensively  use  the Statisrica  (kernel  release  5.5A for  Windows), with  a
     few  exceptions, for  illustrating  PR  methods  with  appropriate  examples  and  real
     data.


        8 .-
       , r:!                                                      A
                                                                   -
       iYALue                                                      A +
        NU~V~
                         3     4       5      6      7     8     9-
                 AiT I  N  I  PRT I  ARM  I  PRM  IARTGI  NG  /PRI
       i48  1  117        76   492    2  46   6  47  33  0  3  0  40










     Figure  1.14.  S~a~isrica scroll-sheet  for  the  cork  stoppers  data.  Each  row
     corresponds  to  a  pattern.  C  is  the  class  label  column.  The  other  columns
     correspond to the features.
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