weka.classifiers
Class OneR

java.lang.Object
  |
  +--weka.classifiers.Classifier
        |
        +--weka.classifiers.OneR

All Implemented Interfaces:

java.lang.Cloneable, OptionHandler, java.io.Serializable

public class OneR

extends Classifier

implements OptionHandler

Class for building and using a 1R classifier. For more information, see

R.C. Holte (1993). Very simple classification rules perform well on most commonly used datasets. Machine Learning, Vol. 11, pp. 63-91.

Valid options are:

-B num
Specify the minimum number of objects in a bucket (default: 6).

Author:

Ian H. Witten (ihw@cs.waikato.ac.nz)

See Also:

Serialized Form

Constructor Summary

OneR()

Method Summary

void	buildClassifier(Instances instances) Generates the classifier.
double	classifyInstance(Instance inst) Classifies a given instance.
int	getMinBucketSize() Get the value of minBucketSize.
java.lang.String[]	getOptions() Gets the current settings of the OneR classifier.
java.util.Enumeration	listOptions() Returns an enumeration describing the available options.
static void	main(java.lang.String[] argv) Main method for testing this class
weka.classifiers.OneR.OneRRule	newNominalRule(Attribute attr, Instances data, int[] missingValueCounts) Create a rule branching on this nominal attribute.
weka.classifiers.OneR.OneRRule	newNumericRule(Attribute attr, Instances data, int[] missingValueCounts) Create a rule branching on this numeric attribute
weka.classifiers.OneR.OneRRule	newRule(Attribute attr, Instances data) Create a rule branching on this attribute.
void	setMinBucketSize(int v) Set the value of minBucketSize.
void	setOptions(java.lang.String[] options) Parses a given list of options.
java.lang.String	toString() Returns a description of the classifier

Methods inherited from class weka.classifiers.Classifier

forName, makeCopies

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

OneR

public OneR()

Method Detail

classifyInstance

public double classifyInstance(Instance inst)

Classifies a given instance.

Overrides:

classifyInstance in class Classifier

Parameters:

inst - the instance to be classified

buildClassifier

public void buildClassifier(Instances instances)
                     throws java.lang.Exception

Generates the classifier.

Overrides:

buildClassifier in class Classifier

Parameters:

instances - the instances to be used for building the classifier

Throws:

java.lang.Exception - if the classifier can't be built successfully

newRule

public weka.classifiers.OneR.OneRRule newRule(Attribute attr,
                                              Instances data)
                                       throws java.lang.Exception

Create a rule branching on this attribute.

Parameters:

attr - the attribute to branch on

data - the data to be used for creating the rule

Throws:

java.lang.Exception - if the rule can't be built successfully

newNominalRule

public weka.classifiers.OneR.OneRRule newNominalRule(Attribute attr,
                                                     Instances data,
                                                     int[] missingValueCounts)
                                              throws java.lang.Exception

Create a rule branching on this nominal attribute.

Parameters:

attr - the attribute to branch on

data - the data to be used for creating the rule

missingValueCounts - to be filled in

Throws:

java.lang.Exception - if the rule can't be built successfully

newNumericRule

public weka.classifiers.OneR.OneRRule newNumericRule(Attribute attr,
                                                     Instances data,
                                                     int[] missingValueCounts)
                                              throws java.lang.Exception

Create a rule branching on this numeric attribute

Parameters:

attr - the attribute to branch on

data - the data to be used for creating the rule

missingValueCounts - to be filled in

Throws:

java.lang.Exception - if the rule can't be built successfully

listOptions

public java.util.Enumeration listOptions()

Returns an enumeration describing the available options.

Specified by:

listOptions in interface OptionHandler

Returns:

an enumeration of all the available options

setOptions

public void setOptions(java.lang.String[] options)
                throws java.lang.Exception

Parses a given list of options. Valid options are:

-B num
Specify the minimum number of objects in a bucket (default: 6).

Specified by:

setOptions in interface OptionHandler

Parameters:

options - the list of options as an array of strings

Throws:

java.lang.Exception - if an option is not supported

getOptions

public java.lang.String[] getOptions()

Gets the current settings of the OneR classifier.

Specified by:

getOptions in interface OptionHandler

Returns:

an array of strings suitable for passing to setOptions

toString

public java.lang.String toString()

Returns a description of the classifier

Overrides:

toString in class java.lang.Object

getMinBucketSize

public int getMinBucketSize()

Get the value of minBucketSize.

Returns:

Value of minBucketSize.

setMinBucketSize

public void setMinBucketSize(int v)

Set the value of minBucketSize.

Parameters:

v - Value to assign to minBucketSize.

main

public static void main(java.lang.String[] argv)

Main method for testing this class