de.lmu.ifi.dbs.elki.algorithm.outlier.spatial

Class CTLuRandomWalkEC<P>

java.lang.Object

de.lmu.ifi.dbs.elki.algorithm.AbstractAlgorithm<R>

de.lmu.ifi.dbs.elki.algorithm.AbstractDistanceBasedAlgorithm<P,OutlierResult>

de.lmu.ifi.dbs.elki.algorithm.outlier.spatial.CTLuRandomWalkEC<P>

Type Parameters:

P - Spatial Vector type

All Implemented Interfaces:

Algorithm, DistanceBasedAlgorithm<P>, OutlierAlgorithm

@Title(value="Random Walk on Exhaustive Combination")
 @Description(value="Spatial Outlier Detection using Random Walk on Exhaustive Combination")
 @Reference(authors="X. Liu, C.-T. Lu, F. Chen",
           title="Spatial outlier detection: random walk based approaches",
           booktitle="Proc. SIGSPATIAL Int. Conf. Advances in Geographic Information Systems",
           url="https://doi.org/10.1145/1869790.1869841",
           bibkey="DBLP:conf/gis/LiuLC10")
public class CTLuRandomWalkEC<P>
extends AbstractDistanceBasedAlgorithm<P,OutlierResult>
implements OutlierAlgorithm

Spatial outlier detection based on random walks.

Note: this method can only handle one-dimensional data, but could probably be easily extended to higher dimensional data by using an distance function instead of the absolute difference.

Reference:

X. Liu, C.-T. Lu, F. Chen
Spatial outlier detection: random walk based approaches
Proc. SIGSPATIAL Int. Conf. Advances in Geographic Information Systems

Since:

0.4.0

Author:

Ahmed Hettab

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CTLuRandomWalkEC.Parameterizer<N> Parameterization class.

Field Summary

Fields

Modifier and Type	Field and Description
private double	alpha Parameter alpha: Attribute difference exponent.
private double	c Parameter c: damping factor.
private int	k Parameter k.
private static Logging	LOG Logger.

Fields inherited from class de.lmu.ifi.dbs.elki.algorithm.AbstractAlgorithm

ALGORITHM_ID

Fields inherited from interface de.lmu.ifi.dbs.elki.algorithm.DistanceBasedAlgorithm

DISTANCE_FUNCTION_ID

Constructor Summary

Constructors

Constructor and Description
CTLuRandomWalkEC(DistanceFunction<? super P> distanceFunction, double alpha, double c, int k) Constructor.

Method Summary

Modifier and Type	Method and Description
TypeInformation[]	getInputTypeRestriction() Get the input type restriction used for negotiating the data query.
protected Logging	getLogger() Get the (STATIC) logger for this class.
OutlierResult	run(Relation<P> spatial, Relation<? extends NumberVector> relation) Run the algorithm.

Methods inherited from class de.lmu.ifi.dbs.elki.algorithm.AbstractDistanceBasedAlgorithm

getDistanceFunction

Methods inherited from class de.lmu.ifi.dbs.elki.algorithm.AbstractAlgorithm

run

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.lmu.ifi.dbs.elki.algorithm.outlier.OutlierAlgorithm

run

Field Detail

LOG

private static final Logging LOG

Logger.

alpha

private double alpha

Parameter alpha: Attribute difference exponent.

c

private double c

Parameter c: damping factor.

k

private int k

Parameter k.

Constructor Detail

CTLuRandomWalkEC

public CTLuRandomWalkEC(DistanceFunction<? super P> distanceFunction,
                        double alpha,
                        double c,
                        int k)

Constructor.

Parameters:

distanceFunction - Distance function

alpha - Alpha parameter

c - C parameter

k - Number of neighbors

Method Detail

run

public OutlierResult run(Relation<P> spatial,
                         Relation<? extends NumberVector> relation)

Run the algorithm.

Parameters:

spatial - Spatial neighborhood relation

relation - Attribute value relation

Returns:

Outlier result

getInputTypeRestriction

public TypeInformation[] getInputTypeRestriction()

Description copied from class: AbstractAlgorithm

Get the input type restriction used for negotiating the data query.

Specified by:

getInputTypeRestriction in interface Algorithm

Specified by:

getInputTypeRestriction in class AbstractAlgorithm<OutlierResult>

Returns:

Type restriction

getLogger

protected Logging getLogger()

Description copied from class: AbstractAlgorithm

Get the (STATIC) logger for this class.

Specified by:

getLogger in class AbstractAlgorithm<OutlierResult>

Returns:

the static logger