Package weka.attributeSelection

Class CheckAttributeSelection

java.lang.Object

weka.core.Check

weka.core.CheckScheme

weka.attributeSelection.CheckAttributeSelection

All Implemented Interfaces:

OptionHandler, RevisionHandler

public class CheckAttributeSelection
extends CheckScheme

Class for examining the capabilities and finding problems with attribute selection schemes. If you implement an attribute selection 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 attribute selection don't exist, but this will help find some common ones.

Typical usage:

java weka.attributeSelection.CheckAttributeSelection -W ASscheme_name -- ASscheme_options

CheckAttributeSelection reports on the following:

• Scheme abilities
  • Possible command line options to the scheme
  • Whether the scheme can predict nominal, numeric, string, date or relational class attributes.
  • Whether the scheme can handle numeric predictor attributes
  • Whether the scheme can handle nominal predictor attributes
  • Whether the scheme can handle string predictor attributes
  • Whether the scheme can handle date predictor attributes
  • Whether the scheme can handle relational predictor attributes
  • Whether the scheme can handle multi-instance data
  • Whether the scheme can handle missing predictor values
  • Whether the scheme can handle missing class values
  • Whether a nominal scheme only handles 2 class problems
  • Whether the scheme can handle instance weights
• Correct functioning
  • Correct initialisation during search (i.e. no result changes when search is performed repeatedly)
  • Whether the scheme alters the data pased to it (number of instances, instance order, instance weights, etc)
• Degenerate cases
  • building scheme with zero instances
  • all but one predictor attribute values missing
  • all predictor attribute values missing
  • all but one class values missing
  • all class values missing

Running CheckAttributeSelection with the debug option set will output the training dataset for any failed tests.

The weka.attributeSelection.AbstractAttributeSelectionTest uses this class to test all the schemes. Any changes here, have to be checked in that abstract test class, too.

Valid options are:

 -D
  Turn on debugging output.
 

 -S
  Silent mode - prints nothing to stdout.
 

 -N <num>
  The number of instances in the datasets (default 20).
 

 -nominal <num>
  The number of nominal attributes (default 2).
 

 -nominal-values <num>
  The number of values for nominal attributes (default 1).
 

 -numeric <num>
  The number of numeric attributes (default 1).
 

 -string <num>
  The number of string attributes (default 1).
 

 -date <num>
  The number of date attributes (default 1).
 

 -relational <num>
  The number of relational attributes (default 1).
 

 -num-instances-relational <num>
  The number of instances in relational/bag attributes (default 10).
 

 -words <comma-separated-list>
  The words to use in string attributes.
 

 -word-separators <chars>
  The word separators to use in string attributes.
 

 -eval name [options]
  Full name and options of the evaluator analyzed.
  eg: weka.attributeSelection.CfsSubsetEval
 

 -search name [options]
  Full name and options of the search method analyzed.
  eg: weka.attributeSelection.Ranker
 

 -test <eval|search>
  The scheme to test, either the evaluator or the search method.
  (Default: eval)
 

 Options specific to evaluator weka.attributeSelection.CfsSubsetEval:
 

 -M
  Treat missing values as a separate value.
 

 -L
  Don't include locally predictive attributes.
 

 Options specific to search method weka.attributeSelection.Ranker:
 

 -P <start set>
  Specify a starting set of attributes.
  Eg. 1,3,5-7.
  Any starting attributes specified are
  ignored during the ranking.
 

 -T <threshold>
  Specify a theshold by which attributes
  may be discarded from the ranking.
 

 -N <num to select>
  Specify number of attributes to select
 

Version:

$Revision: 15517 $

Author:

Len Trigg (trigg@cs.waikato.ac.nz), FracPete (fracpete at waikato dot ac dot nz)

See Also:

• TestInstances

Nested Class Summary

Nested classes/interfaces inherited from class weka.core.CheckScheme

CheckScheme.PostProcessor

Constructor Summary

Constructors

Constructor	Description
CheckAttributeSelection()

Method Summary

Modifier and Type	Method	Description
void	doTests()	Begin the tests, reporting results to System.out
ASEvaluation	getEvaluator()	Get the current evaluator
String[]	getOptions()	Gets the current settings of the CheckAttributeSelection.
String	getRevision()	Returns the revision string.
ASSearch	getSearch()	Get the current search method
boolean	getTestEvaluator()	Gets whether the evaluator is being tested or the search method.
Enumeration<Option>	listOptions()	Returns an enumeration describing the available options.
static void	main(String[] args)	Test method for this class
void	setEvaluator(ASEvaluation value)	Set the evaluator to test.
void	setOptions(String[] options)	Parses a given list of options.
void	setSearch(ASSearch value)	Set the search method to test.
void	setTestEvaluator(boolean value)	Sets whether the evaluator or the search method is being tested.

Methods inherited from class weka.core.CheckScheme

attributeTypeToString, getNumDate, getNumInstances, getNumInstancesRelational, getNumNominal, getNumNumeric, getNumRelational, getNumString, getPostProcessor, getWords, getWordSeparators, hasClasspathProblems, setNumDate, setNumInstances, setNumInstancesRelational, setNumNominal, setNumNumeric, setNumRelational, setNumString, setPostProcessor, setWords, setWordSeparators

Methods inherited from class weka.core.Check

getDebug, getSilent, setDebug, setSilent

Methods inherited from class java.lang.Object

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

Constructor Details

CheckAttributeSelection

public CheckAttributeSelection()

Method Details

listOptions

public Enumeration<Option> listOptions()

Returns an enumeration describing the available options.

Specified by:

listOptions in interface OptionHandler

Overrides:

listOptions in class CheckScheme

Returns:

an enumeration of all the available options.

setOptions

public void setOptions(String[] options)
                throws Exception

Parses a given list of options.

Valid options are:

 -D
  Turn on debugging output.
 

 -S
  Silent mode - prints nothing to stdout.
 

 -N <num>
  The number of instances in the datasets (default 20).
 

 -nominal <num>
  The number of nominal attributes (default 2).
 

 -nominal-values <num>
  The number of values for nominal attributes (default 1).
 

 -numeric <num>
  The number of numeric attributes (default 1).
 

 -string <num>
  The number of string attributes (default 1).
 

 -date <num>
  The number of date attributes (default 1).
 

 -relational <num>
  The number of relational attributes (default 1).
 

 -num-instances-relational <num>
  The number of instances in relational/bag attributes (default 10).
 

 -words <comma-separated-list>
  The words to use in string attributes.
 

 -word-separators <chars>
  The word separators to use in string attributes.
 

 -eval name [options]
  Full name and options of the evaluator analyzed.
  eg: weka.attributeSelection.CfsSubsetEval
 

 -search name [options]
  Full name and options of the search method analyzed.
  eg: weka.attributeSelection.Ranker
 

 -test <eval|search>
  The scheme to test, either the evaluator or the search method.
  (Default: eval)
 

 Options specific to evaluator weka.attributeSelection.CfsSubsetEval:
 

 -M
  Treat missing values as a separate value.
 

 -L
  Don't include locally predictive attributes.
 

 Options specific to search method weka.attributeSelection.Ranker:
 

 -P <start set>
  Specify a starting set of attributes.
  Eg. 1,3,5-7.
  Any starting attributes specified are
  ignored during the ranking.
 

 -T <threshold>
  Specify a theshold by which attributes
  may be discarded from the ranking.
 

 -N <num to select>
  Specify number of attributes to select
 

Specified by:

setOptions in interface OptionHandler

Overrides:

setOptions in class CheckScheme

Parameters:

options - the list of options as an array of strings

Throws:

Exception - if an option is not supported

getOptions

public String[] getOptions()

Gets the current settings of the CheckAttributeSelection.

Specified by:

getOptions in interface OptionHandler

Overrides:

getOptions in class CheckScheme

Returns:

an array of strings suitable for passing to setOptions

doTests

public void doTests()

Begin the tests, reporting results to System.out

Specified by:

doTests in class CheckScheme

setEvaluator

public void setEvaluator(ASEvaluation value)

Set the evaluator to test.

Parameters:

value - the evaluator to use.

getEvaluator

public ASEvaluation getEvaluator()

Get the current evaluator

Returns:

the current evaluator

setSearch

public void setSearch(ASSearch value)

Set the search method to test.

Parameters:

value - the search method to use.

getSearch

public ASSearch getSearch()

Get the current search method

Returns:

the current search method

setTestEvaluator

public void setTestEvaluator(boolean value)

Sets whether the evaluator or the search method is being tested.

Parameters:

value - if true then the evaluator will be tested

getTestEvaluator

public boolean getTestEvaluator()

Gets whether the evaluator is being tested or the search method.

Returns:

true if the evaluator is being tested

getRevision

public String getRevision()

Returns the revision string.

Returns:

the revision

main

public static void main(String[] args)

Test method for this class

Parameters:

args - the commandline parameters