gemclus.linear.LinearWasserstein

class gemclus.linear.LinearWasserstein(n_clusters=3, max_iter=1000, learning_rate=0.001, metric='euclidean', ovo=False, solver='adam', batch_size=None, verbose=False, random_state=None, metric_params=None)[source]

Implementation of the maximisation of the Wasserstein GEMINI using a logistic regression as a clustering distribution \(p(y|x)\).

Parameters:
n_clustersint, default=3

The maximum number of clusters to form as well as the number of output neurons in the neural network.

max_iter: int, default=1000

Maximum number of epochs to perform gradient descent in a single run.

learning_rate: float, default=1e-3

Initial learning rate used. It controls the step-size in updating the weights.

metric: {‘cosine’, ‘euclidean’, ‘l2’,’l1’,’manhattan’,’cityblock’, ‘precomputed’},

default=’euclidean’ The metric to use in combination with the Wasserstein objective. It corresponds to one value of PAIRED_DISTANCES. Currently, all metric parameters are the default ones. If the metric is set to ‘precomputed’, then a custom distance matrix must be passed to the argument y of fit, fit_predict and/or score.

ovo: bool, default=False

Whether to run the model using the Wasserstein OvA (False) or the Wasserstein OvO (True).

solver: {‘sgd’,’adam’}, default=’adam’

The solver for weight optimisation.

  • ‘sgd’ refers to stochastic gradient descent.

  • ‘adam’ refers to a stochastic gradient-based optimiser proposed by Kingma, Diederik and Jimmy Ba.

batch_size: int, default=None

The size of batches during gradient descent training. If set to None, the whole data will be considered.

verbose: bool, default=False

Whether to print progress messages to stdout

random_state: int, RandomState instance, default=None

Determines random number generation for weights and bias initialisation. Pass an int for reproducible results across multiple function calls.

metric_params: dict, default=None

A dictionary of keyword arguments to pass to the chosen metric function.

Attributes:
W_: ndarray of shape (n_features_in, n_clusters)

The linear weights of model

b_: ndarray of shape (1, n_clusters)

The biases of the model

optimiser_: `AdamOptimizer` or `SGDOptimizer`

The optimisation algorithm used for training depending on the chosen solver parameter.

labels_: ndarray of shape (n_samples)

The labels that were assigned to the samples passed to the fit() method.

n_iter_: int

The number of iterations that the model took for converging.

See also

LinearModel

logistic regression trained for clustering with any GEMINI

LinearMMD

logistic regression trained for clustering with the MMD GEMINI

RIM

logistic regression trained with a regularised mutual information

References

GEMINI - Generalised Mutual Information for Discriminative Clustering

Louis Ohl, Pierre-Alexandre Mattei, Charles Bouveyron, Warith Harchaoui, Mickaël Leclercq, Arnaud Droit, Frederic Precioso

Examples

>>> from sklearn.datasets import load_iris
>>> from gemclus.linear import LinearWasserstein
>>> X,y=load_iris(return_X_y=True)
>>> clf = LinearWasserstein(random_state=0).fit(X)
>>> clf.predict(X[:2,:])
array([0, 0])
>>> clf.predict_proba(X[:2,:]).shape
(2, 3)
>>> clf.score(X)
1.7103992986
__init__(n_clusters=3, max_iter=1000, learning_rate=0.001, metric='euclidean', ovo=False, solver='adam', batch_size=None, verbose=False, random_state=None, metric_params=None)[source]
fit(X, y=None)

Compute GEMINI clustering.

Parameters:
X{array-like, sparse matrix} of shape (n_samples, n_features)

Training instances to cluster.

yndarray of shape (n_samples, n_samples), default=None

Use this parameter to give a precomputed affinity metric if the option “precomputed” was passed during construction. Otherwise, it is not used and present here for API consistency by convention.

Returns:
selfobject

Fitted estimator.

fit_predict(X, y=None)

Compute GEMINI clustering and returns the predicted clusters.

Parameters:
X{array-like, sparse matrix} of shape (n_samples, n_features)

Training instances to cluster.

yndarray of shape (n_samples, n_samples), default=None

Use this parameter to give a precomputed affinity metric if the option “precomputed” was passed during construction. Otherwise, it is not used and present here for API consistency by convention.

Returns:
y_predndarray of shape (n_samples,)

Vector containing the cluster label for each sample.

get_gemini()[source]

Initialise a gemclus.GEMINI instance that will be used to train the model.

Returns:
gemini: a GEMINI instance
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_params(deep=True)

Get parameters for this estimator.

Parameters:
deepbool, default=True

If True, will return the parameters for this estimator and contained subobjects that are estimators.

Returns:
paramsdict

Parameter names mapped to their values.

predict(X)

Return the cluster membership of samples. This can only be called after the model was fit to some data.

Parameters:
X{array-like, sparse matrix}, shape (n_samples, n_features)

The input samples.

Returns:
yndarray of shape (n_samples,)

The label for each sample is the label of the closest sample seen during fit.

predict_proba(X)

Probability estimates that are the output of the neural network p(y|x). The returned estimates for all classes are ordered by the label of classes.

Parameters:
X{array-like, sparse matrix} of shape (n_samples, n_features)

Vector to be scored, where n_samples is the number of samples and n_features is the number of features.

Returns:
Tarray-like of shape (n_samples, n_clusters)

Returns the probability of the sample for each cluster in the model.

score(X, y=None)

Return the value of the GEMINI evaluated on the given test data.

Parameters:
X{array-like, sparse matrix} of shape (n_samples, n_features)

Test samples.

yndarray of shape (n_samples, n_samples), default=None

Use this parameter to give a precomputed affinity metric if the option “precomputed” was passed during construction. Otherwise, it is not used and present here for API consistency by convention.

Returns:
scorefloat

GEMINI evaluated on the output of self.predict(X).

set_params(**params)

Set the parameters of this estimator.

The method works on simple estimators as well as on nested objects (such as Pipeline). The latter have parameters of the form <component>__<parameter> so that it’s possible to update each component of a nested object.

Parameters:
**paramsdict

Estimator parameters.

Returns:
selfestimator instance

Estimator instance.

Examples using gemclus.linear.LinearWasserstein

Example of decision boundary map for a mixture of Gaussian and low-degree Student distributions

Example of decision boundary map for a mixture of Gaussian and low-degree Student distributions