Note

This page is a reference documentation. It only explains the class signature, and not how to use it. Please refer to the What you really need to know section for the big picture.

julearn.model_selection.ContinuousStratifiedGroupKFold

class julearn.model_selection.ContinuousStratifiedGroupKFold(n_bins, method='binning', n_splits=5, shuffle=False, random_state=None)

Stratified Group K-Fold cross validator for regression problems.

Stratified Group K-Fold, where stratification is done based on the discretization of the target variable into a fixed number of bins/quantiles.

Parameters:

n_binsint

Number of bins/quantiles to use.

methodstr, default=”binning”

Method used to stratify the groups. Can be either “binning” or “quantile”. In the first case, the groups are stratified by binning the target variable. In the second case, the groups are stratified by quantiling the target variable.

n_splitsint, default=5

Number of folds. Must be at least 2.

shufflebool, default=False

Whether to shuffle each class’s samples before splitting into batches. Note that the samples within each split will not be shuffled. This implementation can only shuffle groups that have approximately the same y distribution, no global shuffle will be performed.

random_stateint or RandomState instance, default=None

When shuffle is True, random_state affects the ordering of the indices, which controls the randomness of each fold for each class. Otherwise, leave random_state as None. Pass an int for reproducible output across multiple function calls.

Notes

Randomized CV splitters may return different results for each call of split. You can make the results identical by setting random_state to an integer.

__init__(n_bins, method='binning', n_splits=5, shuffle=False, random_state=None)

split(X, y, groups=None)

Generate indices to split data into training and test set.

Parameters:

Xarray-like of shape (n_samples, n_features)

Training data, where n_samples is the number of samples and n_features is the number of features. Note that providing y is sufficient to generate the splits and hence np.zeros(n_samples) may be used as a placeholder for X instead of actual training data.

yarray-like of shape (n_samples,), default=None

The target variable for supervised learning problems.

groupsarray-like of shape (n_samples,), default=None

Group labels for the samples used while splitting the dataset into train/test set.

Yields:

trainndarray

The training set indices for that split.

testndarray

The testing set indices for that split.

Notes

Randomized CV splitters may return different results for each call of split. You can make the results identical by setting random_state to an integer.

get_metadata_routing()

Get metadata routing of this object.

Please check User Guide on how the routing mechanism works.

Returns:

routingMetadataRequest

A MetadataRequest encapsulating routing information.

get_n_splits(X=None, y=None, groups=None)

Returns the number of splitting iterations in the cross-validator.

Parameters:

Xobject

Always ignored, exists for compatibility.

yobject

Always ignored, exists for compatibility.

groupsobject

Always ignored, exists for compatibility.

Returns:

n_splitsint

Returns the number of splitting iterations in the cross-validator.

set_split_request(*, groups='$UNCHANGED$')

Configure whether metadata should be requested to be passed to the split method.

Note that this method is only relevant when this estimator is used as a sub-estimator within a meta-estimator and metadata routing is enabled with enable_metadata_routing=True (see sklearn.set_config()). Please check the User Guide on how the routing mechanism works.

The options for each parameter are:

• True: metadata is requested, and passed to split if provided. The request is ignored if metadata is not provided.

• False: metadata is not requested and the meta-estimator will not pass it to split.

• None: metadata is not requested, and the meta-estimator will raise an error if the user provides it.

• str: metadata should be passed to the meta-estimator with this given alias instead of the original name.

The default (sklearn.utils.metadata_routing.UNCHANGED) retains the existing request. This allows you to change the request for some parameters and not others.

Added in version 1.3.

Parameters:

groupsstr, True, False, or None, default=sklearn.utils.metadata_routing.UNCHANGED

Metadata routing for groups parameter in split.

Returns:

selfobject

The updated object.