KNNDD (ELKI: Environment for DeveLoping KDD-Applications Supported by Index-Structures)

java.lang.Object
- elki.outlier.distance.KNNDD<O>

Type Parameters:

O - the type of objects processed by this algorithm

All Implemented Interfaces:

Algorithm, OutlierAlgorithm
```
@Title("KNNDD: k-Nearest Neighbor Data Description")
@Reference(authors="D. de Ridder, D. M. J. Tax, R. P. W. Duin",
           title="An experimental comparison of one-class classification methods",
           booktitle="Proc. 4th Ann. Conf. Advanced School for Computing and Imaging (ASCI\'98)",
           url="http://prlab.tudelft.nl/sites/default/files/asci_98.pdf",
           bibkey="conf/asci/deRidderTD98")
public class KNNDD<O>
extends java.lang.Object
implements OutlierAlgorithm
```
Nearest Neighbor Data Description.
A variation inbetween of KNN outlier and LOF, comparing the nearest neighbor distance of a point to the nearest neighbor distance of the nearest neighbor.
The initial description used k=1, where this equation makes most sense. For k > 1, one may want to use averaging similar to LOF.
Reference ("1-Nearest-Neighbor method"):
D. de Ridder, D. M. J. Tax, R. P. W. Duin
An experimental comparison of one-class classification methods
Proc. 4th Ann. Conf. Advanced School for Computing and Imaging (ASCI'98)

Since:

0.7.5

Author:

Erich Schubert

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class KNNDD.Par<O>
Parameterization class.
- Nested classes/interfaces inherited from interface elki.Algorithm
  Algorithm.Utils

Field Summary

Fields
Modifier and Type	Field	Description
`protected Distance<? super O>`	`distance`	Distance function used.
`protected int`	`kplus`	The parameter k (plus query point!)
`private static Logging`	`LOG`	The logger for this class.

Constructor Summary

Constructors
Constructor Description

KNNDD(Distance<? super O> distance, int k)
Constructor for a single kNN query.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`TypeInformation[]`	`getInputTypeRestriction()`	Get the input type restriction used for negotiating the data query.
`OutlierResult`	`run(Relation<O> relation)`	Runs the algorithm in the timed evaluation part.

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
```
protected Distance<? super O> distance
```
    Distance function used.
  - kplus
```
protected int kplus
```
    The parameter k (plus query point!)
- Constructor Detail
  - KNNDD
```
public KNNDD(Distance<? super O> distance,
             int k)
```
    Constructor for a single kNN query.
    
    Parameters:
    
    distance - distance function to use
    
    k - Value of k (excluding query point!)
- 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> relation)
```
    Runs the algorithm in the timed evaluation part.
    
    Parameters:
    
    relation - Data relation