weka.filters.unsupervised.attribute
Class AddNoise

java.lang.Object
  |
  +--weka.filters.Filter
        |
        +--weka.filters.unsupervised.attribute.AddNoise

All Implemented Interfaces:

OptionHandler, java.io.Serializable, UnsupervisedFilter

public class AddNoise

extends Filter

implements UnsupervisedFilter, OptionHandler

Introduces noise data a random subsample of the dataset by changing a given attribute (attribute must be nominal) Valid options are:

-C col
Index of the attribute to be changed. (default last)

-M
flag: missing values are treated as an extra value

-P num
Percentage of noise to be introduced to the data (default 10).

-S seed
Random number seed for choosing the data to be changed

and for choosing the value it is changed to (default 1).

Version:

$Revision: 1.2 $

Author:

Gabi Schmidberger (gabi@cs.waikato.ac.nz)

See Also:

Serialized Form

Constructor Summary

AddNoise()

Method Summary

void	addNoise(Instances instances, int seed, int percent, int attIndex, boolean useMissing) add noise to the dataset a given percentage of the instances are changed in the way, that a set of instances are randomly selected using seed.
java.lang.String	attIndexSetTipText() Returns the tip text for this property
boolean	batchFinished() Signify that this batch of input to the filter is finished.
java.lang.String	getAttributeIndex() Get the index of the attribute used.
java.lang.String[]	getOptions() Gets the current settings of the filter.
int	getPercent() Gets the size of noise data as a percentage of the original set.
int	getRandomSeed() Gets the random number seed.
boolean	getUseMissing() Gets the flag if missing values are treated as extra values.
java.lang.String	globalInfo() Returns a string describing this filter
boolean	input(Instance instance) Input an instance for filtering.
java.util.Enumeration	listOptions() Returns an enumeration describing the available options
static void	main(java.lang.String[] argv) Main method for testing this class.
java.lang.String	percentTipText() Returns the tip text for this property
java.lang.String	randomSeedTipText() Returns the tip text for this property
void	setAttributeIndex(java.lang.String attIndex) Sets index of the attribute used.
boolean	setInputFormat(Instances instanceInfo) Sets the format of the input instances.
void	setOptions(java.lang.String[] options) Parses a list of options for this object.
void	setPercent(int newPercent) Sets the size of noise data, as a percentage of the original set.
void	setRandomSeed(int newSeed) Sets the random number seed.
void	setUseMissing(boolean newUseMissing) Sets the flag if missing values are treated as extra values.
java.lang.String	useMissingTipText() Returns the tip text for this property

Methods inherited from class weka.filters.Filter

batchFilterFile, filterFile, getOutputFormat, inputFormat, isOutputFormatDefined, numPendingOutput, output, outputFormat, outputPeek, useFilter

Methods inherited from class java.lang.Object

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

Constructor Detail

AddNoise

public AddNoise()

Method Detail

globalInfo

public java.lang.String globalInfo()

Returns a string describing this filter

Returns:

a description of the filter suitable for displaying in the explorer/experimenter gui

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 list of options for this object. Valid options are:

-C col
Index of the attribute to be changed. (default last)

-M
missing values are treated as an extra value

-P num
Specify the percentage of noise introduced to the data (default 10).

-S num
Specify the random number seed (default 1).

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 filter.

Specified by:

getOptions in interface OptionHandler

Returns:

an array of strings suitable for passing to setOptions

useMissingTipText

public java.lang.String useMissingTipText()

Returns the tip text for this property

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

getUseMissing

public boolean getUseMissing()

Gets the flag if missing values are treated as extra values.

Returns:

the flag missing values.

setUseMissing

public void setUseMissing(boolean newUseMissing)

Sets the flag if missing values are treated as extra values.

Parameters:

newUseMissing - the new flag value.

randomSeedTipText

public java.lang.String randomSeedTipText()

Returns the tip text for this property

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

getRandomSeed

public int getRandomSeed()

Gets the random number seed.

Returns:

the random number seed.

setRandomSeed

public void setRandomSeed(int newSeed)

Sets the random number seed.

Parameters:

newSeed - the new random number seed.

percentTipText

public java.lang.String percentTipText()

Returns the tip text for this property

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

getPercent

public int getPercent()

Gets the size of noise data as a percentage of the original set.

Returns:

the noise data size

setPercent

public void setPercent(int newPercent)

Sets the size of noise data, as a percentage of the original set.

Parameters:

newPercent - the subsample set size, between 0 and 100.

attIndexSetTipText

public java.lang.String attIndexSetTipText()

Returns the tip text for this property

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

getAttributeIndex

public java.lang.String getAttributeIndex()

Get the index of the attribute used.

Returns:

the index of the attribute

setAttributeIndex

public void setAttributeIndex(java.lang.String attIndex)

Sets index of the attribute used.

setInputFormat

public boolean setInputFormat(Instances instanceInfo)
                       throws java.lang.Exception

Sets the format of the input instances.

Overrides:

setInputFormat in class Filter

Parameters:

instanceInfo - an Instances object containing the input instance structure (any instances contained in the object are ignored - only the structure is required).

Returns:

true if the outputFormat may be collected immediately

Throws:

java.lang.Exception - if the input format can't be set successfully

input

public boolean input(Instance instance)
              throws java.lang.Exception

Input an instance for filtering.

Overrides:

input in class Filter

Parameters:

instance - the input instance

Returns:

true if the filtered instance may now be collected with output().

Throws:

java.lang.Exception - if the input format was not set

batchFinished

public boolean batchFinished()
                      throws java.lang.Exception

Signify that this batch of input to the filter is finished. If the filter requires all instances prior to filtering, output() may now be called to retrieve the filtered instances.

Overrides:

batchFinished in class Filter

Returns:

true if there are instances pending output

Throws:

java.lang.Exception - if no input structure has been defined

addNoise

public void addNoise(Instances instances,
                     int seed,
                     int percent,
                     int attIndex,
                     boolean useMissing)

add noise to the dataset a given percentage of the instances are changed in the way, that a set of instances are randomly selected using seed. The attribute given by its index is changed from its current value to one of the other possibly ones, also randomly. This is done with leaving the apportion the same. if m_UseMissing is true, missing value is used as a value of its own

Parameters:

instances - is the dataset

seed - used for random function

percent - percentage of instances that are changed

attIndex - index of the attribute changed

main

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

Main method for testing this class.

Parameters:

argv - should contain arguments to the filter: use -h for help