Package weka.classifiers

Class CrossValidationHelper

java.lang.Object

weka.classifiers.CrossValidationHelper

public class CrossValidationHelper
extends Object

Helper class for cross-validation.

Version:

$Revision$

Author:

FracPete (fracpete at waikato dot ac dot nz)

Field Summary

Fields

Modifier and Type	Field	Description
static String	PLACEHOLDER_CURRENTFOLD	the placeholder for the current fold number.
static String	PLACEHOLDER_ORIGINAL	the placeholder for the (original) relation name.
static String	PLACEHOLDER_TYPE	the placeholder for "train" or "test" type.

Constructor Summary

Constructors

Constructor	Description
CrossValidationHelper()

Method Summary

Modifier and Type	Method	Description
static int[]	alignIndices(int[] original)	Reorders the indices to align with the original data.
static ArrayList<weka.classifiers.evaluation.Prediction>	alignPredictions(ArrayList<weka.classifiers.evaluation.Prediction> predictions, int[] original)	Reorders the predictions to align with the original data.
static String	createRelationName(String relation, String template, int fold, boolean train)	Generates a relation name for the current fold.
static int[]	crossValidationIndices(weka.core.Instances data, int folds, Random random)	Returns the indices from the original dataset for tracing the predictions back to the original dataset (stratified).
static int[]	crossValidationIndices(weka.core.Instances data, int folds, Random random, boolean stratify)	Returns the indices from the original dataset for tracing the predictions back to the original dataset.
static String	relationNameTemplateTipText()	Returns the tiptext for the relation name template.

Methods inherited from class java.lang.Object

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

Field Detail

PLACEHOLDER_ORIGINAL

public static final String PLACEHOLDER_ORIGINAL

the placeholder for the (original) relation name.

See Also:

Constant Field Values

PLACEHOLDER_TYPE

public static final String PLACEHOLDER_TYPE

the placeholder for "train" or "test" type.

See Also:

Constant Field Values

PLACEHOLDER_CURRENTFOLD

public static final String PLACEHOLDER_CURRENTFOLD

the placeholder for the current fold number.

See Also:

Constant Field Values

Constructor Detail

CrossValidationHelper

public CrossValidationHelper()

Method Detail

crossValidationIndices

public static int[] crossValidationIndices(weka.core.Instances data,
                                           int folds,
                                           Random random)

Returns the indices from the original dataset for tracing the predictions back to the original dataset (stratified).

Parameters:

data - the original data

folds - the number of folds

random - the random number generator

Returns:

the indices

crossValidationIndices

public static int[] crossValidationIndices(weka.core.Instances data,
                                           int folds,
                                           Random random,
                                           boolean stratify)

Returns the indices from the original dataset for tracing the predictions back to the original dataset.

Parameters:

data - the original data

folds - the number of folds

random - the random number generator

stratify - whether to stratify

Returns:

the indices

alignIndices

public static int[] alignIndices(int[] original)

Reorders the indices to align with the original data.

Parameters:

original - the original indices

Returns:

the aligned data

alignPredictions

public static ArrayList<weka.classifiers.evaluation.Prediction> alignPredictions(ArrayList<weka.classifiers.evaluation.Prediction> predictions,
                                                                                 int[] original)

Reorders the predictions to align with the original data.

Parameters:

predictions - the predictions to align

original - the original indices

Returns:

the aligned data

createRelationName

public static String createRelationName(String relation,
                                        String template,
                                        int fold,
                                        boolean train)

Generates a relation name for the current fold.

Parameters:

relation - the original relation name

template - the template for the relation name

fold - the current fold

train - whether train or test set

Returns:

the relation name

relationNameTemplateTipText

public static String relationNameTemplateTipText()

Returns the tiptext for the relation name template.

Returns:

the tiptext

See Also:

createRelationName(String, String, int, boolean)