RankSearch

java.lang.Object
- weka.attributeSelection.ASSearch
- - weka.attributeSelection.RankSearch

All Implemented Interfaces:

java.io.Serializable, OptionHandler, RevisionHandler, TechnicalInformationHandler
```
public class RankSearch
extends ASSearch
implements OptionHandler, TechnicalInformationHandler
```
RankSearch :

Uses an attribute/subset evaluator to rank all attributes. If a subset evaluator is specified, then a forward selection search is used to generate a ranked list. From the ranked list of attributes, subsets of increasing size are evaluated, ie. The best attribute, the best attribute plus the next best attribute, etc.... The best attribute set is reported. RankSearch is linear in the number of attributes if a simple attribute evaluator is used such as GainRatioAttributeEval. For more information see:

Mark Hall, Geoffrey Holmes (2003). Benchmarking attribute selection techniques for discrete class data mining. IEEE Transactions on Knowledge and Data Engineering. 15(6):1437-1447.
Valid options are:
```
 -A <attribute evaluator>
  class name of attribute evaluator to use for ranking. Place any
  evaluator options LAST on the command line following a "--".
  eg.:
   -A weka.attributeSelection.GainRatioAttributeEval ... -- -M
  (default: weka.attributeSelection.GainRatioAttributeEval)
```
```
 -S <step size>
  number of attributes to be added from the
  ranking in each iteration (default = 1).
```
```
 -R <start point>
  point in the ranking to start evaluating from. 
  (default = 0, ie. the head of the ranking).
```
```
 
 Options specific to evaluator weka.attributeSelection.GainRatioAttributeEval:
 
```
```
 -M
  treat missing values as a seperate value.
```
Version:

$Revision: 6253 $

Author:

Mark Hall (mhall@cs.waikato.ac.nz)

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor and Description

RankSearch()
Constructor

Constructors
Constructor and Description
`RankSearch()` Constructor

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`java.lang.String`	`attributeEvaluatorTipText()` Returns the tip text for this property
`ASEvaluation`	`getAttributeEvaluator()` Get the attribute evaluator used to generate the ranking.
`java.lang.String[]`	`getOptions()` Gets the current settings of WrapperSubsetEval.
`java.lang.String`	`getRevision()` Returns the revision string.
`int`	`getStartPoint()` Get the point at which to start evaluating the ranking
`int`	`getStepSize()` Get the number of attributes to add from the rankining in each iteration
`TechnicalInformation`	`getTechnicalInformation()` Returns an instance of a TechnicalInformation object, containing detailed information about the technical background of this class, e.g., paper reference or book this class is based on.
`java.lang.String`	`globalInfo()` Returns a string describing this search method
`java.util.Enumeration`	`listOptions()` Returns an enumeration describing the available options.
`int[]`	`search(ASEvaluation ASEval, Instances data)` Ranks attributes using the specified attribute evaluator and then searches the ranking using the supplied subset evaluator.
`void`	`setAttributeEvaluator(ASEvaluation newEvaluator)` Set the attribute evaluator to use for generating the ranking.
`void`	`setOptions(java.lang.String[] options)` Parses a given list of options.
`void`	`setStartPoint(int sp)` Set the point at which to start evaluating the ranking
`void`	`setStepSize(int ss)` Set the number of attributes to add from the rankining in each iteration
`java.lang.String`	`startPointTipText()` Returns the tip text for this property
`java.lang.String`	`stepSizeTipText()` Returns the tip text for this property
`java.lang.String`	`toString()` returns a description of the search as a String

Methods inherited from class weka.attributeSelection.ASSearch
forName, makeCopies

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - RankSearch
```
public RankSearch()
```
    Constructor
- Method Detail
  - globalInfo
```
public java.lang.String globalInfo()
```
    Returns a string describing this search method
    
    Returns:
    
    a description of the search method suitable for displaying in the explorer/experimenter gui
  - getTechnicalInformation
```
public TechnicalInformation getTechnicalInformation()
```
    Returns an instance of a TechnicalInformation object, containing detailed information about the technical background of this class, e.g., paper reference or book this class is based on.
    
    Specified by:
    
    getTechnicalInformation in interface TechnicalInformationHandler
    
    Returns:
    
    the technical information about this class
  - attributeEvaluatorTipText
```
public java.lang.String attributeEvaluatorTipText()
```
    Returns the tip text for this property
    
    Returns:
    
    tip text for this property suitable for displaying in the explorer/experimenter gui
  - setAttributeEvaluator
```
public void setAttributeEvaluator(ASEvaluation newEvaluator)
```
    Set the attribute evaluator to use for generating the ranking.
    
    Parameters:
    
    newEvaluator - the attribute evaluator to use.
  - getAttributeEvaluator
```
public ASEvaluation getAttributeEvaluator()
```
    Get the attribute evaluator used to generate the ranking.
    
    Returns:
    
    the evaluator used to generate the ranking.
  - stepSizeTipText
```
public java.lang.String stepSizeTipText()
```
    Returns the tip text for this property
    
    Returns:
    
    tip text for this property suitable for displaying in the explorer/experimenter gui
  - setStepSize
```
public void setStepSize(int ss)
```
    Set the number of attributes to add from the rankining in each iteration
    
    Parameters:
    
    ss - the number of attribes to add.
  - getStepSize
```
public int getStepSize()
```
    Get the number of attributes to add from the rankining in each iteration
    
    Returns:
    
    the number of attributes to add.
  - startPointTipText
```
public java.lang.String startPointTipText()
```
    Returns the tip text for this property
    
    Returns:
    
    tip text for this property suitable for displaying in the explorer/experimenter gui
  - setStartPoint
```
public void setStartPoint(int sp)
```
    Set the point at which to start evaluating the ranking
    
    Parameters:
    
    sp - the position in the ranking to start at
  - getStartPoint
```
public int getStartPoint()
```
    Get the point at which to start evaluating the ranking
    
    Returns:
    
    the position in the ranking to start at
  - 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:
```
 -A <attribute evaluator>
  class name of attribute evaluator to use for ranking. Place any
  evaluator options LAST on the command line following a "--".
  eg.:
   -A weka.attributeSelection.GainRatioAttributeEval ... -- -M
  (default: weka.attributeSelection.GainRatioAttributeEval)
```
```
 -S <step size>
  number of attributes to be added from the
  ranking in each iteration (default = 1).
```
```
 -R <start point>
  point in the ranking to start evaluating from. 
  (default = 0, ie. the head of the ranking).
```
```
 
 Options specific to evaluator weka.attributeSelection.GainRatioAttributeEval:
 
```
```
 -M
  treat missing values as a seperate value.
```
    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 WrapperSubsetEval.
    
    Specified by:
    
    getOptions in interface OptionHandler
    
    Returns:
    
    an array of strings suitable for passing to setOptions()
  - search
```
public int[] search(ASEvaluation ASEval,
                    Instances data)
             throws java.lang.Exception
```
    Ranks attributes using the specified attribute evaluator and then searches the ranking using the supplied subset evaluator.
    
    Specified by:
    
    search in class ASSearch
    
    Parameters:
    
    ASEval - the subset evaluator to guide the search
    
    data - the training instances.
    
    Returns:
    
    an array (not necessarily ordered) of selected attribute indexes
    
    Throws:
    
    java.lang.Exception - if the search can't be completed
  - toString
```
public java.lang.String toString()
```
    returns a description of the search as a String
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    a description of the search
  - getRevision
```
public java.lang.String getRevision()
```
    Returns the revision string.
    
    Specified by:
    
    getRevision in interface RevisionHandler
    
    Overrides:
    
    getRevision in class ASSearch
    
    Returns:
    
    the revision

Class RankSearch

Constructor Summary

Method Summary

Methods inherited from class weka.attributeSelection.ASSearch

Methods inherited from class java.lang.Object

Constructor Detail

RankSearch

Method Detail

globalInfo

getTechnicalInformation

attributeEvaluatorTipText

setAttributeEvaluator

getAttributeEvaluator

stepSizeTipText

setStepSize

getStepSize

startPointTipText

setStartPoint

getStartPoint

listOptions

setOptions

getOptions

search

toString

getRevision