Package weka.classifiers.trees.j48

Class NBTreeNoSplit

java.lang.Object

weka.classifiers.trees.j48.ClassifierSplitModel

weka.classifiers.trees.j48.NBTreeNoSplit

All Implemented Interfaces:

Serializable, Cloneable, RevisionHandler

public final class NBTreeNoSplit
extends ClassifierSplitModel

Class implementing a "no-split"-split (leaf node) for naive bayes trees.

Version:

$Revision$

Author:

Mark Hall (mhall@cs.waikato.ac.nz)

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
NBTreeNoSplit()

Method Summary

Modifier and Type	Method	Description
void	buildClassifier(Instances instances)	Build the no-split node
double	classProb(int classIndex, Instance instance, int theSubset)	Return the probability for a class value
static double	crossValidate(NaiveBayesUpdateable fullModel, Instances trainingSet, Random r)	Utility method for fast 5-fold cross validation of a naive bayes model
Discretize	getDiscretizer()	Return the discretizer used at this node
double	getErrors()	Return the errors made by the naive bayes model at this node
NaiveBayesUpdateable	getNaiveBayesModel()	Get the naive bayes model at this node
String	getRevision()	Returns the revision string.
String	leftSide(Instances instances)	Does nothing because no condition has to be satisfied.
String	rightSide(int index, Instances instances)	Does nothing because no condition has to be satisfied.
String	sourceExpression(int index, Instances data)	Returns a string containing java source code equivalent to the test made at this node.
String	toString()	Return a textual description of the node
double[]	weights(Instance instance)	Always returns null because there is only one subset.
int	whichSubset(Instance instance)	Always returns 0 because only there is only one subset.

Methods inherited from class weka.classifiers.trees.j48.ClassifierSplitModel

checkModel, classifyInstance, classProbLaplace, clone, codingCost, distribution, dumpLabel, dumpModel, numSubsets, resetDistribution, setDistribution, sourceClass, split

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

NBTreeNoSplit

public NBTreeNoSplit()

Method Detail

buildClassifier

public final void buildClassifier(Instances instances)
                           throws Exception

Build the no-split node

Specified by:

buildClassifier in class ClassifierSplitModel

Parameters:

instances - an Instances value

Throws:

Exception - if an error occurs

getErrors

public double getErrors()

Return the errors made by the naive bayes model at this node

Returns:

the number of errors made

getDiscretizer

public Discretize getDiscretizer()

Return the discretizer used at this node

Returns:

a Discretize value

getNaiveBayesModel

public NaiveBayesUpdateable getNaiveBayesModel()

Get the naive bayes model at this node

Returns:

a NaiveBayesUpdateable value

whichSubset

public final int whichSubset(Instance instance)

Always returns 0 because only there is only one subset.

Specified by:

whichSubset in class ClassifierSplitModel

weights

public final double[] weights(Instance instance)

Always returns null because there is only one subset.

Specified by:

weights in class ClassifierSplitModel

leftSide

public final String leftSide(Instances instances)

Does nothing because no condition has to be satisfied.

Specified by:

leftSide in class ClassifierSplitModel

Parameters:

instances - the data.

rightSide

public final String rightSide(int index,
                              Instances instances)

Does nothing because no condition has to be satisfied.

Specified by:

rightSide in class ClassifierSplitModel

sourceExpression

public final String sourceExpression(int index,
                                     Instances data)

Returns a string containing java source code equivalent to the test made at this node. The instance being tested is called "i".

Specified by:

sourceExpression in class ClassifierSplitModel

Parameters:

index - index of the nominal value tested

data - the data containing instance structure info

Returns:

a value of type 'String'

classProb

public double classProb(int classIndex,
                        Instance instance,
                        int theSubset)
                 throws Exception

Return the probability for a class value

Overrides:

classProb in class ClassifierSplitModel

Parameters:

classIndex - the index of the class value

instance - the instance to generate a probability for

theSubset - the subset to consider

Returns:

a probability

Throws:

Exception - if an error occurs

toString

public String toString()

Return a textual description of the node

Overrides:

toString in class Object

Returns:

a String value

crossValidate

public static double crossValidate(NaiveBayesUpdateable fullModel,
                                   Instances trainingSet,
                                   Random r)
                            throws Exception

Utility method for fast 5-fold cross validation of a naive bayes model

Parameters:

fullModel - a NaiveBayesUpdateable value

trainingSet - an Instances value

r - a Random value

Returns:

a double value

Throws:

Exception - if an error occurs

getRevision

public String getRevision()

Returns the revision string.

Returns:

the revision