Package weka.classifiers.trees.ht

Class NominalConditionalSufficientStats

java.lang.Object

weka.classifiers.trees.ht.ConditionalSufficientStats

weka.classifiers.trees.ht.NominalConditionalSufficientStats

All Implemented Interfaces:

Serializable

public class NominalConditionalSufficientStats
extends ConditionalSufficientStats
implements Serializable

Maintains sufficient stats for the distribution of a nominal attribute

Version:

$Revision$

Author:

Richard Kirkby (rkirkby@cs.waikato.ac.nz), Mark Hall (mhall{[at]}pentaho{[dot]}com)

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
NominalConditionalSufficientStats()

Method Summary

Modifier and Type	Method	Description
SplitCandidate	bestSplit(SplitMetric splitMetric, Map<String,WeightMass> preSplitDist, String attName)	Return the best split
double	probabilityOfAttValConditionedOnClass(double attVal, String classVal)	Return the probability of an attribute value conditioned on a class value
void	update(double attVal, String classVal, double weight)	Update this stat with the supplied attribute value and class value

Methods inherited from class java.lang.Object

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

Constructor Detail

NominalConditionalSufficientStats

public NominalConditionalSufficientStats()

Method Detail

update

public void update(double attVal,
                   String classVal,
                   double weight)

Description copied from class: ConditionalSufficientStats

Update this stat with the supplied attribute value and class value

Specified by:

update in class ConditionalSufficientStats

Parameters:

attVal - the value of the attribute

classVal - the class value

weight - the weight of this observation

probabilityOfAttValConditionedOnClass

public double probabilityOfAttValConditionedOnClass(double attVal,
                                                    String classVal)

Description copied from class: ConditionalSufficientStats

Return the probability of an attribute value conditioned on a class value

Specified by:

probabilityOfAttValConditionedOnClass in class ConditionalSufficientStats

Parameters:

attVal - the attribute value to compute the conditional probability for

classVal - the class value

Returns:

the probability

bestSplit

public SplitCandidate bestSplit(SplitMetric splitMetric,
                                Map<String,WeightMass> preSplitDist,
                                String attName)

Description copied from class: ConditionalSufficientStats

Return the best split

Specified by:

bestSplit in class ConditionalSufficientStats

Parameters:

splitMetric - the split metric to use

preSplitDist - the distribution of class values prior to splitting

attName - the name of the attribute being considered for splitting

Returns:

the best split for the attribute