weka.classifiers
Class CheckClassifier

java.lang.Object
  |
  +--weka.classifiers.CheckClassifier

All Implemented Interfaces:

OptionHandler

public class CheckClassifier

extends java.lang.Object

implements OptionHandler

Class for examining the capabilities and finding problems with classifiers. If you implement a classifier using the WEKA.libraries, you should run the checks on it to ensure robustness and correct operation. Passing all the tests of this object does not mean bugs in the classifier don't exist, but this will help find some common ones.

Typical usage:

java weka.classifiers.CheckClassifier -W classifier_name classifier_options

CheckClassifier reports on the following:

• Classifier abilities
  • Possible command line options to the classifier
  • Whether the classifier can predict nominal and/or predict numeric class attributes. Warnings will be displayed if performance is worse than ZeroR
  • Whether the classifier can be trained incrementally
  • Whether the classifier can handle numeric predictor attributes
  • Whether the classifier can handle nominal predictor attributes
  • Whether the classifier can handle string predictor attributes
  • Whether the classifier can handle missing predictor values
  • Whether the classifier can handle missing class values
  • Whether a nominal classifier only handles 2 class problems
  • Whether the classifier can handle instance weights
• Correct functioning
  • Correct initialisation during buildClassifier (i.e. no result changes when buildClassifier called repeatedly)
  • Whether incremental training produces the same results as during non-incremental training (which may or may not be OK)
  • Whether the classifier alters the data pased to it (number of instances, instance order, instance weights, etc)
• Degenerate cases
  • building classifier with zero training instances
  • all but one predictor attribute values missing
  • all predictor attribute values missing
  • all but one class values missing
  • all class values missing

Running CheckClassifier with the debug option set will output the training and test datasets for any failed tests.

Valid options are:

-D
Turn on debugging output.

-W classname
Specify the full class name of a classifier to perform the tests on (required).

Options after -- are passed to the designated classifier.

Version:

$Revision: 1.15 $

Author:

Len Trigg (trigg@cs.waikato.ac.nz)

Constructor Summary

CheckClassifier()

Method Summary

void	doTests() Begin the tests, reporting results to System.out
Classifier	getClassifier() Get the classifier used as the classifier
boolean	getDebug() Get whether debugging is turned on
java.lang.String[]	getOptions() Gets the current settings of the CheckClassifier.
java.util.Enumeration	listOptions() Returns an enumeration describing the available options.
static void	main(java.lang.String[] args) Test method for this class
void	setClassifier(Classifier newClassifier) Set the classifier for boosting.
void	setDebug(boolean debug) Set debugging mode
void	setOptions(java.lang.String[] options) Parses a given list of options.

Methods inherited from class java.lang.Object

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

Constructor Detail

CheckClassifier

public CheckClassifier()

Method Detail

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:

-D
Turn on debugging output.

-W classname
Specify the full class name of a classifier to perform the tests on (required).

Options after -- are passed to the designated classifier

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 CheckClassifier.

Specified by:

getOptions in interface OptionHandler

Returns:

an array of strings suitable for passing to setOptions

doTests

public void doTests()

Begin the tests, reporting results to System.out

setDebug

public void setDebug(boolean debug)

Set debugging mode

Parameters:

debug - true if debug output should be printed

getDebug

public boolean getDebug()

Get whether debugging is turned on

Returns:

true if debugging output is on

setClassifier

public void setClassifier(Classifier newClassifier)

Set the classifier for boosting.

Parameters:

newClassifier - the Classifier to use.

getClassifier

public Classifier getClassifier()

Get the classifier used as the classifier

Returns:

the classifier used as the classifier

main

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

Test method for this class