org.openimaj.experiment.validation.cross

Class StratifiedGroupedKFold<KEY,INSTANCE>

java.lang.Object

org.openimaj.experiment.validation.cross.StratifiedGroupedKFold<KEY,INSTANCE>

Type Parameters:

KEY - Type of groups

INSTANCE - Type of instances

All Implemented Interfaces:

CrossValidator<GroupedDataset<KEY,ListDataset<INSTANCE>,INSTANCE>>

public class StratifiedGroupedKFold<KEY,INSTANCE>
extends Object
implements CrossValidator<GroupedDataset<KEY,ListDataset<INSTANCE>,INSTANCE>>

Stratified K-Fold Cross-Validation on grouped datasets.

This implementation randomly splits the data in each group into K non-overlapping subsets. The number of folds, K, is set at the size of the smallest group if it is bigger; this ensures that each fold will contain at least one training and validation example for each group, and that the relative distribution of instances per group for each fold is approximately the same as for the full dataset.

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

Constructor Summary

Constructors

Constructor and Description
StratifiedGroupedKFold(int k) Construct a StratifiedGroupedKFold with the given target number of folds, K.

Method Summary

Modifier and Type	Method and Description
CrossValidationIterable<GroupedDataset<KEY,ListDataset<INSTANCE>,INSTANCE>>	createIterable(GroupedDataset<KEY,ListDataset<INSTANCE>,INSTANCE> data) Create the iterable from the dataset.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

StratifiedGroupedKFold

public StratifiedGroupedKFold(int k)

Construct a StratifiedGroupedKFold with the given target number of folds, K. If a group in the dataset has fewer than K instances, then the number of folds will be reduced to the number of instances.

Parameters:

k - the target number of folds.

Method Detail

createIterable

public CrossValidationIterable<GroupedDataset<KEY,ListDataset<INSTANCE>,INSTANCE>> createIterable(GroupedDataset<KEY,ListDataset<INSTANCE>,INSTANCE> data)

Description copied from interface: CrossValidator

Create the iterable from the dataset.

Specified by:

createIterable in interface CrossValidator<GroupedDataset<KEY,ListDataset<INSTANCE>,INSTANCE>>

Parameters:

data - the dataset

Returns:

the iterable

toString

public String toString()

Overrides:

toString in class Object