Package weka.associations

Class CheckAssociator

java.lang.Object

weka.core.Check

weka.core.CheckScheme

weka.associations.CheckAssociator

All Implemented Interfaces:

OptionHandler, RevisionHandler

public class CheckAssociator
extends CheckScheme
implements RevisionHandler

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

Typical usage:

java weka.associations.CheckAssociator -W associator_name -- associator_options

CheckAssociator reports on the following:

• Associator abilities
  • Possible command line options to the associators
  • Whether the associators can predict nominal, numeric, string, date or relational class attributes.
  • Whether the associators can handle numeric predictor attributes
  • Whether the associators can handle nominal predictor attributes
  • Whether the associators can handle string predictor attributes
  • Whether the associators can handle date predictor attributes
  • Whether the associators can handle relational predictor attributes
  • Whether the associators can handle multi-instance data
  • Whether the associators can handle missing predictor values
  • Whether the associators can handle missing class values
  • Whether a nominal associators only handles 2 class problems
  • Whether the associators can handle instance weights
• Correct functioning
  • Correct initialisation during buildAssociations (i.e. no result changes when buildAssociations called repeatedly)
  • Whether the associators alters the data pased to it (number of instances, instance order, instance weights, etc)
• Degenerate cases
  • building associators 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 CheckAssociator with the debug option set will output the training dataset for any failed tests.

The weka.associations.AbstractAssociatorTest uses this class to test all the associators. 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.
 

 -W
  Full name of the associator analysed.
  eg: weka.associations.Apriori
  (default weka.associations.Apriori)
 

 Options specific to associator weka.associations.Apriori:
 

 -N <required number of rules output>
  The required number of rules. (default = 10)
 

 -T <0=confidence | 1=lift | 2=leverage | 3=Conviction>
  The metric type by which to rank rules. (default = confidence)
 

 -C <minimum metric score of a rule>
  The minimum confidence of a rule. (default = 0.9)
 

 -D <delta for minimum support>
  The delta by which the minimum support is decreased in
  each iteration. (default = 0.05)
 

 -U <upper bound for minimum support>
  Upper bound for minimum support. (default = 1.0)
 

 -M <lower bound for minimum support>
  The lower bound for the minimum support. (default = 0.1)
 

 -S <significance level>
  If used, rules are tested for significance at
  the given level. Slower. (default = no significance testing)
 

 -I
  If set the itemsets found are also output. (default = no)
 

 -R
  Remove columns that contain all missing values (default = no)
 

 -V
  Report progress iteratively. (default = no)
 

 -A
  If set class association rules are mined. (default = no)
 

 -c <the class index>
  The class index. (default = last)
 

Options after -- are passed to the designated associator.

Version:

$Revision: 11247 $

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

Field Summary

Fields

Modifier and Type	Field	Description
static final int	NO_CLASS	a "dummy" class type

Constructor Summary

Constructors

Constructor	Description
CheckAssociator()

Method Summary

Modifier and Type	Method	Description
void	doTests()	Begin the tests, reporting results to System.out
Associator	getAssociator()	Get the associator being tested
String[]	getOptions()	Gets the current settings of the CheckAssociator.
String	getRevision()	Returns the revision string.
Enumeration<Option>	listOptions()	Returns an enumeration describing the available options.
static void	main(String[] args)	Test method for this class
void	setAssociator(Associator newAssociator)	Set the associator to test.
void	setOptions(String[] options)	Parses a given list of options.

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

Field Details

NO_CLASS

public static final int NO_CLASS

a "dummy" class type

See Also:

• Constant Field Values

Constructor Details

CheckAssociator

public CheckAssociator()

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.
 

 -W
  Full name of the associator analysed.
  eg: weka.associations.Apriori
  (default weka.associations.Apriori)
 

 Options specific to associator weka.associations.Apriori:
 

 -N <required number of rules output>
  The required number of rules. (default = 10)
 

 -T <0=confidence | 1=lift | 2=leverage | 3=Conviction>
  The metric type by which to rank rules. (default = confidence)
 

 -C <minimum metric score of a rule>
  The minimum confidence of a rule. (default = 0.9)
 

 -D <delta for minimum support>
  The delta by which the minimum support is decreased in
  each iteration. (default = 0.05)
 

 -U <upper bound for minimum support>
  Upper bound for minimum support. (default = 1.0)
 

 -M <lower bound for minimum support>
  The lower bound for the minimum support. (default = 0.1)
 

 -S <significance level>
  If used, rules are tested for significance at
  the given level. Slower. (default = no significance testing)
 

 -I
  If set the itemsets found are also output. (default = no)
 

 -R
  Remove columns that contain all missing values (default = no)
 

 -V
  Report progress iteratively. (default = no)
 

 -A
  If set class association rules are mined. (default = no)
 

 -c <the class index>
  The class index. (default = last)
 

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 CheckAssociator.

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

setAssociator

public void setAssociator(Associator newAssociator)

Set the associator to test.

Parameters:

newAssociator - the Associator to use.

getAssociator

public Associator getAssociator()

Get the associator being tested

Returns:

the associator being tested

getRevision

public String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Returns:

the revision

main

public static void main(String[] args)

Test method for this class

Parameters:

args - the commandline parameters