AI::Categorizer::Learner::SVM--3pm

AI::Categorizer::LearnUserSContributed Perl AI::Categorizer::Learner::SVM(3pm)



NAME
       AI::Categorizer::Learner::SVM - Support Vector Machine Learner

SYNOPSIS
         use AI::Categorizer::Learner::SVM;

         # Here $k is an AI::Categorizer::KnowledgeSet object

         my $l = new AI::Categorizer::Learner::SVM(...parameters...);
         $l->train(knowledge_set => $k);
         $l->save_state('filename');

         ... time passes ...

         $l = AI::Categorizer::Learner->restore_state('filename');
         while (my $document = ... ) {  # An AI::Categorizer::Document object
           my $hypothesis = $l->categorize($document);
           print "Best assigned category: ", $hypothesis->best_category, "\n";
         }

DESCRIPTION
       This class implements a Support Vector Machine machine learner, using
       Cory Spencer's "Algorithm::SVM" module.  In lots of the recent academic
       literature, SVMs perform very well for text categorization.

METHODS
       This class inherits from the "AI::Categorizer::Learner" class, so all
       of its methods are available unless explicitly mentioned here.

       new()

       Creates a new SVM Learner and returns it.  In addition to the parame-
       ters accepted by the "AI::Categorizer::Learner" class, the SVM subclass
       accepts the following parameters:

       svm_kernel
           Specifies what type of kernel should be used when building the SVM.
           Default is 'linear'.  Possible values are 'linear', 'polynomial',
           'radial' and 'sigmoid'.

       train(knowledge_set => $k)

       Trains the categorizer.  This prepares it for later use in categorizing
       documents.  The "knowledge_set" parameter must provide an object of the
       class "AI::Categorizer::KnowledgeSet" (or a subclass thereof), popu-
       lated with lots of documents and categories.  See AI::Catego-
       rizer::KnowledgeSet for the details of how to create such an object.

       categorize($document)

       Returns an "AI::Categorizer::Hypothesis" object representing the cate-
       gorizer's "best guess" about which categories the given document should
       be assigned to.  See AI::Categorizer::Hypothesis for more details on
       how to use this object.

       save_state($path)

       Saves the categorizer for later use.  This method is inherited from
       "AI::Categorizer::Storable".

AUTHOR
       Ken Williams, ken AT mathforum.org

COPYRIGHT
       Copyright 2000-2003 Ken Williams.  All rights reserved.

       This library is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

SEE ALSO
       AI::Categorizer(3), Algorithm::SVM(3)



perl v5.8.7                       2002-11-24AI::Categorizer::Learner::SVM(3pm)