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

java.lang.Object
- elki.outlier.density.HySortOD

All Implemented Interfaces:

elki.Algorithm, OutlierAlgorithm
```
@Title("HySortOD: Hypercube-Based Outlier Detection")
@Description("Algorithm that uses an efficient hypercube-ordering-and-searching strategy for fast outlier detection.")
@Reference(authors="Eug\u00eanio F. Cabral, and Robson L.F. Cordeiro",
           title="Fast and Scalable Outlier Detection with Sorted Hypercubes",
           booktitle="Proc. 29th ACM Int. Conf. on Information & Knowledge Management (CIKM\'20)",
           url="https://doi.org/10.1145/3340531.3412033")
public class HySortOD
extends java.lang.Object
implements OutlierAlgorithm
```
Hypercube-Based Outlier Detection.
Algorithm that uses an efficient hypercube-ordering-and-searching strategy for fast outlier detection. Its main focus is the analysis of data with many instances and a low-to-moderate number of dimensions.
Reference:
Eugênio F. Cabral and Robson L.F. Cordeiro
Fast and Scalable Outlier Detection with Sorted Hypercubes
Proc. 29th ACM Int. Conf. on Information and Knowledge Management (CIKM'20)

Since:

0.8.0

Author:

Cabral, Eugênio F. (Original Code), Braulio V.S. Vinces (ELKIfication)

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`private static class`	`HySortOD.DensityStrategy`	Strategy for compute density.
`private static class`	`HySortOD.Hypercube`	Bounded regions of the space where at least one instance exists.
`private static class`	`HySortOD.NaiveStrategy`	Naive strategy for computing density.
`private static class`	`HySortOD.TreeStrategy`	Tree strategy for computing density.

Nested classes/interfaces inherited from interface elki.Algorithm
elki.Algorithm.Utils

Field Summary

Fields
Modifier and Type	Field	Description
`private int`	`b`	Number of bins.
`private double`	`l`	Hypercube's length.
`private static elki.logging.Logging`	`LOG`	The logger for this class.
`private HySortOD.DensityStrategy`	`strategy`	Strategy for hypercubes density search.

Constructor Summary

Constructors
Constructor Description

HySortOD(int b, int minSplit)
Constructor with parameters.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`elki.data.type.TypeInformation[]`	`getInputTypeRestriction()`
`private java.util.List<HySortOD.Hypercube>`	`getSortedHypercubes(elki.database.relation.Relation<? extends elki.data.NumberVector> relation)`	Create and sort hypercubes considering their coordinates.
`OutlierResult`	`run(elki.database.Database db, elki.database.relation.Relation<? extends elki.data.NumberVector> relation)`
`private double`	`score(int density)`	Compute score according to hypercube neighborhood density.

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 elki.logging.Logging LOG
```
    The logger for this class.
  - b
```
private int b
```
    Number of bins.
  - l
```
private final double l
```
    Hypercube's length.
  - strategy
```
private HySortOD.DensityStrategy strategy
```
    Strategy for hypercubes density search.
- Constructor Detail
  - HySortOD
```
public HySortOD(int b,
                int minSplit)
```
    Constructor with parameters.
    
    Parameters:
    
    b - Number of bins
    
    minSplit - Threshold to balance the tree strategy
- Method Detail
  - run
```
public OutlierResult run(elki.database.Database db,
                         elki.database.relation.Relation<? extends elki.data.NumberVector> relation)
```
  - getSortedHypercubes
```
private java.util.List<HySortOD.Hypercube> getSortedHypercubes(elki.database.relation.Relation<? extends elki.data.NumberVector> relation)
```
    Create and sort hypercubes considering their coordinates.
    
    Parameters:
    
    relation - Data to process
    
    Returns:
    
    Hypercubes sorted
  - score
```
private double score(int density)
```
    Compute score according to hypercube neighborhood density.
    
    Parameters:
    
    density - Hypercube density
    
    Returns:
    
    score
  - getInputTypeRestriction
```
public elki.data.type.TypeInformation[] getInputTypeRestriction()
```
    Specified by:
    
    getInputTypeRestriction in interface elki.Algorithm