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

java.lang.Object
- elki.outlier.spatial.AbstractNeighborhoodOutlier<N>
- - elki.outlier.spatial.AbstractDistanceBasedSpatialOutlier<N,O>
  - - elki.outlier.spatial.SOF<N,O>

Type Parameters:

N - Neighborhood object type

O - Attribute object type

All Implemented Interfaces:

Algorithm, OutlierAlgorithm
```
@Title("Spatial Outlier Factor")
@Reference(authors="T. Huang, X. Qin",
           title="Detecting outliers in spatial database",
           booktitle="Proc. 3rd International Conference on Image and Graphics",
           url="https://doi.org/10.1109/ICIG.2004.53",
           bibkey="DBLP:conf/icig/HuangQ04")
public class SOF<N,O>
extends AbstractDistanceBasedSpatialOutlier<N,O>
```
The Spatial Outlier Factor (SOF) is a spatial LOF variation.
Since the "reachability distance" of LOF cannot be used canonically in the bichromatic case, this part of LOF is dropped and the exact distance is used instead.
Reference:
T. Huang, X. Qin
Detecting outliers in spatial database
Proc. 3rd International Conference on Image and Graphics
A LOF variation simplified with reachDist(o,p) == dist(o,p).

Since:

0.4.0

Author:

Ahmed Hettab

Nested Class Summary
- Nested classes/interfaces inherited from interface elki.Algorithm
  Algorithm.Utils

Field Summary
- Fields inherited from class elki.outlier.spatial.AbstractNeighborhoodOutlier
  NEIGHBORHOOD_ID

Constructor Summary

Constructors
Constructor Description

SOF(NeighborSetPredicate.Factory<N> npred, PrimitiveDistance<O> nonSpatialDistance)
Constructor.

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(Database database, Relation<N> spatial, Relation<O> relation)`	The main run method

Methods inherited from class elki.outlier.spatial.AbstractDistanceBasedSpatialOutlier
getNonSpatialDistance

Methods inherited from class elki.outlier.spatial.AbstractNeighborhoodOutlier
getNeighborSetPredicateFactory

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

- Constructor Detail
  - SOF
```
public SOF(NeighborSetPredicate.Factory<N> npred,
           PrimitiveDistance<O> nonSpatialDistance)
```
    Constructor.
    
    Parameters:
    
    npred - Neighborhood predicate
    
    nonSpatialDistance - Distance function on non-spatial attributes
- Method Detail
  - getInputTypeRestriction
```
public TypeInformation[] getInputTypeRestriction()
```
    Description copied from interface: Algorithm
    
    Get the input type restriction used for negotiating the data query.
    
    Returns:
    
    Type restriction
  - run
```
public OutlierResult run(Database database,
                         Relation<N> spatial,
                         Relation<O> relation)
```
    The main run method
    
    Parameters:
    
    database - Database to use (actually unused)
    
    spatial - Relation for neighborhood
    
    relation - Attributes to evaluate
    
    Returns:
    
    Outlier result