Package elki.outlier.spatial

Class CTLuRandomWalkEC<O>

java.lang.Object

elki.outlier.spatial.CTLuRandomWalkEC<O>

Type Parameters:

O - object type

All Implemented Interfaces:

Algorithm, OutlierAlgorithm

@Title("Random Walk on Exhaustive Combination")
@Description("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<O>
extends java.lang.Object
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/interfaces inherited from interface elki.Algorithm

Algorithm.Utils

Field Summary

Fields

Modifier and Type	Field	Description
private double	alpha	Parameter alpha: Attribute difference exponent.
private double	c	Parameter c: damping factor.
private Distance<? super O>	distance	Distance function used.
private int	k	Parameter k.
private static Logging	LOG	Class logger

Constructor Summary

Constructors

Constructor	Description
CTLuRandomWalkEC(Distance<? super O> distance, double alpha, double c, int k)	Constructor.

Method Summary

Modifier and Type	Method	Description
TypeInformation[]	getInputTypeRestriction()	Get the input type restriction used for negotiating the data query.
OutlierResult	run(Relation<O> spatial, Relation<? extends NumberVector> relation)	Run the algorithm.

Methods inherited from class java.lang.Object

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

Methods inherited from interface elki.outlier.OutlierAlgorithm

autorun

Field Detail

LOG

private static final Logging LOG

Class logger

distance

private Distance<? super O> distance

Distance function used.

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(Distance<? super O> distance,
                        double alpha,
                        double c,
                        int k)

Constructor.

Parameters:

distance - Distance function

alpha - Alpha parameter

c - C parameter

k - Number of neighbors

Method Detail

getInputTypeRestriction

public TypeInformation[] getInputTypeRestriction()

Description copied from interface: Algorithm

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

Specified by:

getInputTypeRestriction in interface Algorithm

Returns:

Type restriction

run

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

Run the algorithm.

Parameters:

spatial - Spatial neighborhood relation

relation - Attribute value relation

Returns:

Outlier result