AI::Categorizer::Learner::Boolean--3pm

AI::Categorizer::LearnUserBContributed PAI::Categorizer::Learner::Boolean(3pm)



NAME
       AI::Categorizer::Learner::Boolean - Abstract class for boolean catego-
       rizers

SYNOPSIS
        package AI::Categorizer::Learner::SomethingNew;
        use AI::Categorizer::Learner::Boolean;
        @ISA = qw(AI::Categorizer::Learner::Boolean);

        sub create_boolean_model {
          my ($self, $positives, $negatives, $category) = @_;
          ...
          return $something_helpful;
        }

        sub get_boolean_score {
          my ($self, $document, $something_helpful) = @_;
          ...
          return $score;
        }

DESCRIPTION
       This is an abstract class which turns boolean categorizers (categoriz-
       ers based on algorithms that can just provide yes/no categorization
       decisions for a single document and single category) into multi-valued
       categorizers.  For instance, the decision tree categorizer "AI::Catego-
       rizer::Learner::DecisionTree" maintains a decision tree for each cate-
       gory, then uses it to decide whether a certain document belongs to the
       given category.

       Any class that inherits from this class should implement the following
       methods:

       create_boolean_model()

       Used during training to create a category-specific model.  The type of
       model you create is up to you - it should be returned as a scalar.
       Whatever you return will be available to you in the
       "get_boolean_score()" method, so put any information you'll need during
       categorization in this scalar.

       In addition to $self, this method will be passed three arguments.  The
       first argument is a reference to an array of positive examples, i.e.
       documents that belong to the given category.  The next argument is a
       reference to an array of negative examples, i.e. documents that do not
       belong to the given category.  The final argument is the Category
       object for the given category.

       get_boolean_score()

       Used during categorization to assign a score for a single document rel-
       ative to a single category.  The score should be between 0 and 1, with
       a score greater than 0.5 indicating membership in the category.

       In addition to $self, this method will be passed two arguments.  The
       first argument is the document to be categorized.  The second argument
       is the value returned by "create_boolean_model()" for this category.

AUTHOR
       Ken Williams, <ken AT mathforum.org>

SEE ALSO
       AI::Categorizer



perl v5.8.7                       2002-1AI::Categorizer::Learner::Boolean(3pm)