Package elki.outlier.lof

Class ALOCI<V extends NumberVector>

java.lang.Object

elki.outlier.lof.ALOCI<V>

Type Parameters:

V - Vector type

All Implemented Interfaces:

Algorithm, OutlierAlgorithm

@Title("Approximate LOCI: Fast Outlier Detection Using the Local Correlation Integral")
@Description("Algorithm to compute outliers based on the Local Correlation Integral")
@Reference(authors="S. Papadimitriou, H. Kitagawa, P. B. Gibbons, C. Faloutsos",
           title="LOCI: Fast Outlier Detection Using the Local Correlation Integral",
           booktitle="Proc. 19th IEEE Int. Conf. on Data Engineering (ICDE \'03)",
           url="https://doi.org/10.1109/ICDE.2003.1260802",
           bibkey="DBLP:conf/icde/PapadimitriouKGF03")
public class ALOCI<V extends NumberVector>
extends java.lang.Object
implements OutlierAlgorithm

Fast Outlier Detection Using the "approximate Local Correlation Integral".

Outlier detection using multiple epsilon neighborhoods.

Reference:

S. Papadimitriou, H. Kitagawa, P. B. Gibbons and C. Faloutsos:
LOCI: Fast Outlier Detection Using the Local Correlation Integral.
In: Proc. 19th IEEE Int. Conf. on Data Engineering (ICDE '03)

Since:

0.5.0

Author:

Jonathan von Brünken, Erich Schubert

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	ALOCI.ALOCIQuadTree	Simple quadtree for ALOCI.
(package private) static class	ALOCI.Node	Node of the ALOCI Quadtree
static class	ALOCI.Par<O extends NumberVector>	Parameterization class.

Nested classes/interfaces inherited from interface elki.Algorithm

Algorithm.Utils

Field Summary

Fields

Modifier and Type	Field	Description
private int	alpha	Alpha (level difference of sampling and counting neighborhoods)
private NumberVectorDistance<? super V>	distance	Distance function used.
private int	g	Number of trees to generate (forest size)
private static Logging	LOG	The logger for this class.
private int	nmin	Minimum size for a leaf.
private RandomFactory	rnd	Random generator

Constructor Summary

Constructors

Constructor	Description
ALOCI(NumberVectorDistance<? super V> distance, int nmin, int alpha, int g, RandomFactory rnd)	Constructor.

Method Summary

Modifier and Type	Method	Description
private static double	calculate_MDEF_norm(ALOCI.Node sn, ALOCI.Node cg)	Method for the MDEF calculation
TypeInformation[]	getInputTypeRestriction()	Get the input type restriction used for negotiating the data query.
OutlierResult	run(Relation<V> 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

The logger for this class.

distance

private NumberVectorDistance<? super V extends NumberVector> distance

Distance function used.

nmin

private int nmin

Minimum size for a leaf.

alpha

private int alpha

Alpha (level difference of sampling and counting neighborhoods)

g

private int g

Number of trees to generate (forest size)

rnd

private RandomFactory rnd

Random generator

Constructor Detail

ALOCI

public ALOCI(NumberVectorDistance<? super V> distance,
             int nmin,
             int alpha,
             int g,
             RandomFactory rnd)

Constructor.

Parameters:

distance - Distance function

nmin - Minimum neighborhood size

alpha - Alpha value

g - Number of grids to use

rnd - Random generator.

Method Detail

run

public OutlierResult run(Relation<V> relation)

Run the algorithm.

Parameters:

relation - Relation to process

Returns:

Outlier detection result

calculate_MDEF_norm

private static double calculate_MDEF_norm(ALOCI.Node sn,
                                          ALOCI.Node cg)

Method for the MDEF calculation

Parameters:

sn - Sampling Neighborhood

cg - Counting Neighborhood

Returns:

MDEF norm

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