LOF

java.lang.Object
- weka.filters.Filter
- - weka.filters.unsupervised.attribute.LOF

All Implemented Interfaces:: java.io.Serializable, weka.core.CapabilitiesHandler, weka.core.CapabilitiesIgnorer, weka.core.CommandlineRunnable, weka.core.EnvironmentHandler, weka.core.OptionHandler, weka.core.RevisionHandler, weka.core.TechnicalInformationHandler, weka.core.WeightedInstancesHandler

public class LOF
extends weka.filters.Filter
implements weka.core.OptionHandler, weka.core.WeightedInstancesHandler, weka.core.TechnicalInformationHandler, weka.core.EnvironmentHandler

A filter that applies the LOF (Local Outlier Factor) algorithm to compute an "outlier" score for each instance in the data. Can use multiple cores/cpus to speed up the LOF computation for large datasets. Nearest neighbor search methods and distance functions are pluggable.

For more information, see:

Markus M. Breunig, Hans-Peter Kriegel, Raymond T. Ng, Jorg Sander (2000). LOF: Identifying Density-Based Local Outliers. ACM SIGMOD Record. 29(2):93-104.

BibTeX:

 @article{Breunig2000,
    author = {Markus M. Breunig and Hans-Peter Kriegel and Raymond T. Ng and Jorg Sander},
    journal = {ACM SIGMOD Record},
    number = {2},
    pages = {93-104},
    publisher = {ACM New York},
    title = {LOF: Identifying Density-Based Local Outliers},
    volume = {29},
    year = {2000}
 }

Valid options are:

 -min <num>
  Lower bound on the k nearest neighbors for finding max LOF (minPtsLB)
  (default = 10)

 -max <num>
  Upper bound on the k nearest neighbors for finding max LOF (minPtsUB)
  (default = 40)

 -A
  The nearest neighbour search algorithm to use (default: weka.core.neighboursearch.LinearNNSearch).

 -num-slots <num>
  Number of execution slots.
  (default 1 - i.e. no parallelism)

Version:: $Revision: 12154 $
Author:: Mark Hall (mhall{[at]}pentaho{[dot]}com)
See Also:: Serialized Form

Constructor Summary

Constructors
Constructor and Description

LOF()

Constructors
Constructor and Description
`LOF()`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`batchFinished()` Signifies that this batch of input to the filter is finished.
`weka.core.Capabilities`	`getCapabilities()` Returns the Capabilities of this filter.
`java.lang.String`	`getMinPointsLowerBound()` Get the lower bound (minPtsLB) to use on the range for k when determining the maximum LOF value
`java.lang.String`	`getMinPointsUpperBound()` Get the upper bound (minPtsUB) to use on the range for k when determining the maximum LOF value
`weka.core.neighboursearch.NearestNeighbourSearch`	`getNNSearch()` Get the nearest neighbor search method to use
`java.lang.String`	`getNumExecutionSlots()` Get the degree of parallelism to use.
`java.lang.String[]`	`getOptions()` Gets the current settings of the filter.
`java.lang.String`	`getRevision()` Returns the revision string.
`weka.core.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 filter
`boolean`	`input(weka.core.Instance instance)` Input an instance for filtering.
`java.util.Enumeration<weka.core.Option>`	`listOptions()` Gets an enumeration describing the available options.
`static void`	`main(java.lang.String[] args)` Main method for testing this class
`java.lang.String`	`minPointsLowerBoundTipText()` Returns the tip text for this property
`java.lang.String`	`minPointsUpperBoundTipText()` Returns the tip text for this property
`java.lang.String`	`NNSearchTipText()` Returns the tip text for this property
`java.lang.String`	`numExecutionSlotsTipText()` Returns the tip text for this property
`void`	`setClassifierMode(boolean cm)` Set whether to work in classifier mode or not.
`void`	`setEnvironment(weka.core.Environment env)` Set environment variables to use
`boolean`	`setInputFormat(weka.core.Instances instanceInfo)` Sets the format of the input instances.
`void`	`setMinPointsLowerBound(java.lang.String pts)` Set the lower bound (minPtsLB) to use on the range for k when determining the maximum LOF value
`void`	`setMinPointsUpperBound(java.lang.String pts)` Set the upper bound (minPtsUB) to use on the range for k when determining the maximum LOF value
`void`	`setNNSearch(weka.core.neighboursearch.NearestNeighbourSearch s)` Set the nearest neighbor search method to use
`void`	`setNumExecutionSlots(java.lang.String slots)` Set the degree of parallelism to use.
`void`	`setOptions(java.lang.String[] options)` Parses a given list of options.

Methods inherited from class weka.filters.Filter
batchFilterFile, debugTipText, doNotCheckCapabilitiesTipText, filterFile, getCapabilities, getCopyOfInputFormat, getDebug, getDoNotCheckCapabilities, getOutputFormat, isFirstBatchDone, isNewBatch, isOutputFormatDefined, makeCopies, makeCopy, mayRemoveInstanceAfterFirstBatchDone, numPendingOutput, output, outputPeek, postExecution, preExecution, run, runFilter, setDebug, setDoNotCheckCapabilities, toString, useFilter, wekaStaticWrapper

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

Methods inherited from interface weka.core.OptionHandler
makeCopy

- Constructor Detail
  - LOF
```
public LOF()
```
- 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
  - getCapabilities
```
public weka.core.Capabilities getCapabilities()
```
    Returns the Capabilities of this filter.
    
    Specified by:
    
    getCapabilities in interface weka.core.CapabilitiesHandler
    
    Overrides:
    
    getCapabilities in class weka.filters.Filter
    
    Returns:
    
    the capabilities of this object
    
    See Also:
    
    Capabilities
  - getTechnicalInformation
```
public weka.core.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 weka.core.TechnicalInformationHandler
    
    Returns:
    
    the technical information about this class
  - listOptions
```
public java.util.Enumeration<weka.core.Option> listOptions()
```
    Gets an enumeration describing the available options.
    
    Specified by:
    
    listOptions in interface weka.core.OptionHandler
    
    Overrides:
    
    listOptions in class weka.filters.Filter
    
    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:
```
 -min <num>
  Lower bound on the k nearest neighbors for finding max LOF (minPtsLB)
  (default = 10)
 
```
```
 -max <num>
  Upper bound on the k nearest neighbors for finding max LOF (minPtsUB)
  (default = 40)
 
```
```
 -A
  The nearest neighbour search algorithm to use (default: weka.core.neighboursearch.LinearNNSearch).
 
```
```
 -num-slots <num>
  Number of execution slots.
  (default 1 - i.e. no parallelism)
 
```
    Specified by:
    
    setOptions in interface weka.core.OptionHandler
    
    Overrides:
    
    setOptions in class weka.filters.Filter
    
    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 weka.core.OptionHandler
    
    Overrides:
    
    getOptions in class weka.filters.Filter
    
    Returns:
    
    an array of strings suitable for passing to setOptions
  - setClassifierMode
```
public void setClassifierMode(boolean cm)
```
    Set whether to work in classifier mode or not. In classifier mode the LOF scores for the training data do not need to be computed at training time
    
    Parameters:
    
    cm - true if working as a classifier
  - minPointsLowerBoundTipText
```
public java.lang.String minPointsLowerBoundTipText()
```
    Returns the tip text for this property
    
    Returns:
    
    tip text for this property suitable for displaying in the explorer/experimenter gui
  - setMinPointsLowerBound
```
public void setMinPointsLowerBound(java.lang.String pts)
```
    Set the lower bound (minPtsLB) to use on the range for k when determining the maximum LOF value
    
    Parameters:
    
    pts - the lower bound
  - getMinPointsLowerBound
```
public java.lang.String getMinPointsLowerBound()
```
    Get the lower bound (minPtsLB) to use on the range for k when determining the maximum LOF value
    
    Returns:
    
    the lower bound
  - minPointsUpperBoundTipText
```
public java.lang.String minPointsUpperBoundTipText()
```
    Returns the tip text for this property
    
    Returns:
    
    tip text for this property suitable for displaying in the explorer/experimenter gui
  - setMinPointsUpperBound
```
public void setMinPointsUpperBound(java.lang.String pts)
```
    Set the upper bound (minPtsUB) to use on the range for k when determining the maximum LOF value
    
    Parameters:
    
    pts - the upper bound
  - getMinPointsUpperBound
```
public java.lang.String getMinPointsUpperBound()
```
    Get the upper bound (minPtsUB) to use on the range for k when determining the maximum LOF value
    
    Returns:
    
    the upper bound
  - NNSearchTipText
```
public java.lang.String NNSearchTipText()
```
    Returns the tip text for this property
    
    Returns:
    
    tip text for this property suitable for displaying in the explorer/experimenter gui
  - setNNSearch
```
public void setNNSearch(weka.core.neighboursearch.NearestNeighbourSearch s)
```
    Set the nearest neighbor search method to use
    
    Parameters:
    
    s - the nearest neighbor search method to use
  - getNNSearch
```
public weka.core.neighboursearch.NearestNeighbourSearch getNNSearch()
```
    Get the nearest neighbor search method to use
    
    Returns:
    
    the nearest neighbor search method to use
  - numExecutionSlotsTipText
```
public java.lang.String numExecutionSlotsTipText()
```
    Returns the tip text for this property
    
    Returns:
    
    tip text for this property suitable for displaying in the explorer/experimenter gui
  - setNumExecutionSlots
```
public void setNumExecutionSlots(java.lang.String slots)
```
    Set the degree of parallelism to use.
    
    Parameters:
    
    slots - the number of tasks to run in parallel when computing the nearest neighbors and evaluating different values of k between the lower and upper bounds
  - getNumExecutionSlots
```
public java.lang.String getNumExecutionSlots()
```
    Get the degree of parallelism to use.
    
    Returns:
    
    the number of tasks to run in parallel when computing the nearest neighbors and evaluating different values of k between the lower and upper bounds
  - setInputFormat
```
public boolean setInputFormat(weka.core.Instances instanceInfo)
                       throws java.lang.Exception
```
    Sets the format of the input instances.
    
    Overrides:
    
    setInputFormat in class weka.filters.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(weka.core.Instance instance)
```
    Input an instance for filtering. Ordinarily the instance is processed and made available for output immediately. Some filters require all instances be read before producing output.
    
    Overrides:
    
    input in class weka.filters.Filter
    
    Parameters:
    
    instance - the input instance
    
    Returns:
    
    true if the filtered instance may now be collected with output().
    
    Throws:
    
    java.lang.IllegalStateException - if no input format has been defined.
  - batchFinished
```
public boolean batchFinished()
```
    Signifies 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 weka.filters.Filter
    
    Returns:
    
    true if there are instances pending output
    
    Throws:
    
    java.lang.IllegalStateException - if no input structure has been defined
  - setEnvironment
```
public void setEnvironment(weka.core.Environment env)
```
    Set environment variables to use
    
    Specified by:
    
    setEnvironment in interface weka.core.EnvironmentHandler
    
    Parameters:
    
    env - the evnironment variables to use
  - getRevision
```
public java.lang.String getRevision()
```
    Returns the revision string.
    
    Specified by:
    
    getRevision in interface weka.core.RevisionHandler
    
    Overrides:
    
    getRevision in class weka.filters.Filter
    
    Returns:
    
    the revision
  - main
```
public static void main(java.lang.String[] args)
```
    Main method for testing this class
    
    Parameters:
    
    args - command line arguments

Class LOF

Constructor Summary

Method Summary

Methods inherited from class weka.filters.Filter

Methods inherited from class java.lang.Object

Methods inherited from interface weka.core.OptionHandler

Constructor Detail

LOF

Method Detail

globalInfo

getCapabilities

getTechnicalInformation

listOptions

setOptions

getOptions

setClassifierMode

minPointsLowerBoundTipText

setMinPointsLowerBound

getMinPointsLowerBound

minPointsUpperBoundTipText

setMinPointsUpperBound

getMinPointsUpperBound

NNSearchTipText

setNNSearch

getNNSearch

numExecutionSlotsTipText

setNumExecutionSlots

getNumExecutionSlots

setInputFormat

input

batchFinished

setEnvironment

getRevision

main