Package weka.classifiers.rules

Class JRip.RipperRule

  • All Implemented Interfaces:
    Serializable, Copyable, RevisionHandler, WeightedInstancesHandler
    Enclosing class:
    JRip
    public class JRip.RipperRule
extends Rule
    This class implements a single rule that predicts specified class. A rule consists of antecedents "AND"ed together and the consequent (class value) for the classification. In this class, the Information Gain (p*[log(p/t) - log(P/T)]) is used to select an antecedent and Reduced Error Prunning (REP) with the metric of accuracy rate p/(p+n) or (TP+TN)/(P+N) is used to prune the rule.
    See Also:
    Serialized Form

    • Constructor Detail

      • RipperRule

        public RipperRule()
        Constructor

    • Method Detail

      • cleanUp

        public void cleanUp​(Instances data)
        Removes redundant tests in the rule.
        Parameters:
        data - an instance object that contains the appropriate header information for the attributes.

      • setConsequent

        public void setConsequent​(double cl)
        Sets the internal representation of the class label to be predicted
        Parameters:
        cl - the internal representation of the class label to be predicted

      • getConsequent

        public double getConsequent()
        Gets the internal representation of the class label to be predicted
        Specified by:
        getConsequent in class Rule
        Returns:
        the internal representation of the class label to be predicted

      • copy

        public Object copy()
        Get a shallow copy of this rule
        Specified by:
        copy in interface Copyable
        Overrides:
        copy in class Rule
        Returns:
        the copy

      • covers

        public boolean covers​(Instance datum)
        Whether the instance covered by this rule
        Specified by:
        covers in class Rule
        Parameters:
        datum - the instance in question
        Returns:
        the boolean value indicating whether the instance is covered by this rule

      • hasAntds

        public boolean hasAntds()
        Whether this rule has antecedents, i.e. whether it is a default rule
        Specified by:
        hasAntds in class Rule
        Returns:
        the boolean value indicating whether the rule has antecedents

      • getAntds

        public ArrayList<JRip.Antd> getAntds()
        Return the antecedents
        Returns:
        the vector of antecedents

      • size

        public double size()
        the number of antecedents of the rule
        Specified by:
        size in class Rule
        Returns:
        the size of this rule

      • grow

        public void grow​(Instances data)
          throws Exception
        Build one rule using the growing data
        Specified by:
        grow in class Rule
        Parameters:
        data - the growing data used to build the rule
        Throws:
        Exception - if the consequent is not set yet

      • prune

        public void prune​(Instances pruneData,
                  boolean useWhole)
        Prune all the possible final sequences of the rule using the pruning data. The measure used to prune the rule is based on flag given.
        Parameters:
        pruneData - the pruning data used to prune the rule
        useWhole - flag to indicate whether use the error rate of the whole pruning data instead of the data covered

      • toString

        public String toString​(Attribute classAttr)
        Prints this rule
        Parameters:
        classAttr - the class attribute in the data
        Returns:
        a textual description of this rule

      • getRevision

        public String getRevision()
        Returns the revision string.
        Returns:
        the revision