de.lmu.ifi.dbs.elki.algorithm.statistics
Class EvaluateRankingQuality<V extends RealVector<V,?>,D extends NumberDistance<D,?>>

java.lang.Object
  de.lmu.ifi.dbs.elki.logging.AbstractLoggable
      de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizable
          de.lmu.ifi.dbs.elki.algorithm.AbstractAlgorithm<O,R>
              de.lmu.ifi.dbs.elki.algorithm.DistanceBasedAlgorithm<V,D,CollectionResult<DoubleVector>>
                  de.lmu.ifi.dbs.elki.algorithm.statistics.EvaluateRankingQuality<V,D>

Type Parameters:

V - Vector type

All Implemented Interfaces:

Algorithm<V,CollectionResult<DoubleVector>>, Parameterizable

public class EvaluateRankingQuality<V extends RealVector<V,?>,D extends NumberDistance<D,?>>
extends DistanceBasedAlgorithm<V,D,CollectionResult<DoubleVector>>

Evaluate a distance function with respect to kNN queries. For each point, the neighbors are sorted by distance, then the ROC AUC is computed. A score of 1 means that the distance function provides a perfect ordering of relevant neighbors first, then irrelevant neighbors. A value of 0.5 can be obtained by random sorting. A value of 0 means the distance function is inverted, i.e. a similarity. TODO: Allow fixed binning range, configurable TODO: Add sampling

Author:

Erich Schubert

Field Summary

static OptionID	HISTOGRAM_BINS_ID OptionID for HISTOGRAM_BINS_OPTION
private IntParameter	HISTOGRAM_BINS_OPTION Option to configure the number of bins to use.
(package private) int	numbins Number of bins to use.
private CollectionResult<DoubleVector>	result

Fields inherited from class de.lmu.ifi.dbs.elki.algorithm.DistanceBasedAlgorithm

DISTANCE_FUNCTION_ID, DISTANCE_FUNCTION_PARAM

Fields inherited from class de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizable

optionHandler

Fields inherited from class de.lmu.ifi.dbs.elki.logging.AbstractLoggable

debug, logger

Constructor Summary

EvaluateRankingQuality()
Empty constructor.

Method Summary

Description	getDescription() Describe the algorithm and it's use.
CollectionResult<DoubleVector>	getResult() Return a result object
protected CollectionResult<DoubleVector>	runInTime(Database<V> database) Run the algorithm.
List<String>	setParameters(List<String> args) Calls the super method and instantiates DistanceBasedAlgorithm.distanceFunction according to the value of parameter DistanceBasedAlgorithm.DISTANCE_FUNCTION_PARAM.

Methods inherited from class de.lmu.ifi.dbs.elki.algorithm.DistanceBasedAlgorithm

getDistanceFunction

Methods inherited from class de.lmu.ifi.dbs.elki.algorithm.AbstractAlgorithm

isTime, isVerbose, run, setTime, setVerbose

Methods inherited from class de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizable

addOption, addParameterizable, addParameterizable, checkGlobalParameterConstraints, collectOptions, getAttributeSettings, getParameters, rememberParametersExcept, removeOption, removeParameterizable, shortDescription

Methods inherited from class de.lmu.ifi.dbs.elki.logging.AbstractLoggable

debugFine, debugFiner, debugFinest, exception, progress, verbose, warning

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.lmu.ifi.dbs.elki.utilities.optionhandling.Parameterizable

checkGlobalParameterConstraints, collectOptions, getParameters, shortDescription

Field Detail

result

private CollectionResult<DoubleVector> result

HISTOGRAM_BINS_ID

public static final OptionID HISTOGRAM_BINS_ID

OptionID for HISTOGRAM_BINS_OPTION

HISTOGRAM_BINS_OPTION

private final IntParameter HISTOGRAM_BINS_OPTION

Option to configure the number of bins to use.

numbins

int numbins

Number of bins to use.

Constructor Detail

EvaluateRankingQuality

public EvaluateRankingQuality()

Empty constructor. Nothing to do.

Method Detail

runInTime

protected CollectionResult<DoubleVector> runInTime(Database<V> database)
                                            throws IllegalStateException

Run the algorithm.

Specified by:

runInTime in class AbstractAlgorithm<V extends RealVector<V,?>,CollectionResult<DoubleVector>>

Parameters:

database - the database to run the algorithm on

Returns:

the Result computed by this algorithm

Throws:

IllegalStateException - if the algorithm has not been initialized properly (e.g. the setParameters(String[]) method has been failed to be called).

getDescription

public Description getDescription()

Describe the algorithm and it's use.

Returns:

a description of the algorithm

getResult

public CollectionResult<DoubleVector> getResult()

Return a result object

Returns:

the result of the algorithm

setParameters

public List<String> setParameters(List<String> args)
                           throws ParameterException

Description copied from class: DistanceBasedAlgorithm

Calls the super method and instantiates DistanceBasedAlgorithm.distanceFunction according to the value of parameter DistanceBasedAlgorithm.DISTANCE_FUNCTION_PARAM. The remaining parameters are passed to the DistanceBasedAlgorithm.distanceFunction.

Specified by:

setParameters in interface Parameterizable

Overrides:

setParameters in class DistanceBasedAlgorithm<V extends RealVector<V,?>,D extends NumberDistance<D,?>,CollectionResult<DoubleVector>>

Parameters:

args - parameters to set the attributes accordingly to

Returns:

a list containing the unused parameters

Throws:

ParameterException - in case of wrong parameter-setting