de.lmu.ifi.dbs.elki.evaluation.clustering.internal

Class EvaluateSimplifiedSilhouette

java.lang.Object

de.lmu.ifi.dbs.elki.evaluation.clustering.internal.EvaluateSimplifiedSilhouette

All Implemented Interfaces:

Evaluator, ResultProcessor

public class EvaluateSimplifiedSilhouette
extends Object
implements Evaluator

Compute the simplified silhouette of a data set. The simplified silhouette does not use pairwise distances, but distances to centroids only.

Author:

Stephan Baier, Erich Schubert

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	EvaluateSimplifiedSilhouette.Parameterizer Parameterization class.

Field Summary

Fields

Modifier and Type	Field and Description
private NumberVectorDistanceFunction<?>	distance Distance function to use.
private String	key Key for logging statistics.
private static Logging	LOG Logger for debug output.
private NoiseHandling	noiseOption Option for noise handling.
private boolean	penalize Penalize noise, if NoiseHandling.IGNORE_NOISE is set.

Constructor Summary

Constructors

Constructor and Description
EvaluateSimplifiedSilhouette(NumberVectorDistanceFunction<?> distance, NoiseHandling noiseOpt, boolean penalize) Constructor.

Method Summary

Modifier and Type	Method and Description
static int	centroids(Relation<? extends NumberVector> rel, List<? extends Cluster<?>> clusters, NumberVector[] centroids, NoiseHandling noiseOption) Compute centroids.
double	evaluateClustering(Database db, Relation<? extends NumberVector> rel, Clustering<?> c) Evaluate a single clustering.
void	processNewResult(ResultHierarchy hier, Result result) Process a result.

Methods inherited from class java.lang.Object

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

Field Detail

LOG

private static final Logging LOG

Logger for debug output.

noiseOption

private NoiseHandling noiseOption

Option for noise handling.

distance

private NumberVectorDistanceFunction<?> distance

Distance function to use.

penalize

private boolean penalize

Penalize noise, if NoiseHandling.IGNORE_NOISE is set.

key

private String key

Key for logging statistics.

Constructor Detail

EvaluateSimplifiedSilhouette

public EvaluateSimplifiedSilhouette(NumberVectorDistanceFunction<?> distance,
                                    NoiseHandling noiseOpt,
                                    boolean penalize)

Constructor.

Parameters:

distance - Distance function

noiseOpt - Flag to control noise handling

penalize - noise, if NoiseHandling.IGNORE_NOISE is set.

Method Detail

evaluateClustering

public double evaluateClustering(Database db,
                                 Relation<? extends NumberVector> rel,
                                 Clustering<?> c)

Evaluate a single clustering.

Parameters:

db - Database

rel - Data relation

c - Clustering

Returns:

Mean simplified silhouette

centroids

public static int centroids(Relation<? extends NumberVector> rel,
                            List<? extends Cluster<?>> clusters,
                            NumberVector[] centroids,
                            NoiseHandling noiseOption)

Compute centroids.

Parameters:

rel - Data relation

clusters - Clusters

centroids - Output array for centroids

Returns:

Number of ignored noise elements.

processNewResult

public void processNewResult(ResultHierarchy hier,
                             Result result)

Description copied from interface: ResultProcessor

Process a result.

Specified by:

processNewResult in interface ResultProcessor

Parameters:

hier - The base of the result tree.

result - Newly added result subtree.