de.lmu.ifi.dbs.elki.evaluation.classification.holdout

Class StratifiedCrossValidation

java.lang.Object

de.lmu.ifi.dbs.elki.evaluation.classification.holdout.AbstractHoldout

de.lmu.ifi.dbs.elki.evaluation.classification.holdout.StratifiedCrossValidation

All Implemented Interfaces:

Holdout

public class StratifiedCrossValidation
extends AbstractHoldout

A stratified n-fold crossvalidation to distribute the data to n buckets where each bucket exhibits approximately the same distribution of classes as does the complete data set. The buckets are disjoint. The distribution is deterministic.

Since:

0.7.0

Author:

Arthur Zimek

Nested Class Summary

Nested Classes

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

Field Summary

Fields

Modifier and Type	Field and Description
protected int[]	assignment Partition assignment, sizes
protected int	fold Holds the number of folds, current fold.
protected int	nfold Holds the number of folds, current fold.
protected int[]	sizes Partition assignment, sizes

Fields inherited from class de.lmu.ifi.dbs.elki.evaluation.classification.holdout.AbstractHoldout

bundle, labelcol, labels

Constructor Summary

Constructors

Constructor and Description
StratifiedCrossValidation(int nfold) Provides a stratified crossvalidation.

Method Summary

Modifier and Type	Method and Description
void	initialize(MultipleObjectsBundle bundle) Initialize the holdout procedure for a data set.
TrainingAndTestSet	nextPartitioning() Get the next partitioning of the given holdout.
int	numberOfPartitions() How many partitions to test.

Methods inherited from class de.lmu.ifi.dbs.elki.evaluation.classification.holdout.AbstractHoldout

allClassLabels, allClassLabels, findClassLabelColumn, getLabels

Methods inherited from class java.lang.Object

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

Field Detail

nfold

protected int nfold

Holds the number of folds, current fold.

fold

protected int fold

Holds the number of folds, current fold.

assignment

protected int[] assignment

Partition assignment, sizes

sizes

protected int[] sizes

Partition assignment, sizes

Constructor Detail

StratifiedCrossValidation

public StratifiedCrossValidation(int nfold)

Provides a stratified crossvalidation. Setting parameter N_P to the OptionHandler.

Method Detail

numberOfPartitions

public int numberOfPartitions()

Description copied from interface: Holdout

How many partitions to test.

Returns:

Number of partitions.

initialize

public void initialize(MultipleObjectsBundle bundle)

Description copied from interface: Holdout

Initialize the holdout procedure for a data set.

Specified by:

initialize in interface Holdout

Overrides:

initialize in class AbstractHoldout

Parameters:

bundle - Data set bundle

nextPartitioning

public TrainingAndTestSet nextPartitioning()

Description copied from interface: Holdout

Get the next partitioning of the given holdout.

Returns:

Next partitioning of the data set