Class BaggingClassifierScikitsLearnNode

A Bagging classifier.

This node has been automatically generated by wrapping the ``sklearn.ensemble.bagging.BaggingClassifier`` class
from the ``sklearn`` library.  The wrapped instance can be accessed
through the ``scikits_alg`` attribute.

A Bagging classifier is an ensemble meta-estimator that fits base
classifiers each on random subsets of the original dataset and then
aggregate their individual predictions (either by voting or by averaging)
to form a final prediction. Such a meta-estimator can typically be used as
a way to reduce the variance of a black-box estimator (e.g., a decision
tree), by introducing randomization into its construction procedure and
then making an ensemble out of it.

This algorithm encompasses several works from the literature. When random
subsets of the dataset are drawn as random subsets of the samples, then
this algorithm is known as Pasting [1]_. If samples are drawn with
replacement, then the method is known as Bagging [2]_. When random subsets
of the dataset are drawn as random subsets of the features, then the method
is known as Random Subspaces [3]_. Finally, when base estimators are built
on subsets of both samples and features, then the method is known as
Random Patches [4]_.

Read more in the :ref:`User Guide <bagging>`.

**Parameters**

base_estimator : object or None, optional (default=None)
    The base estimator to fit on random subsets of the dataset.
    If None, then the base estimator is a decision tree.

n_estimators : int, optional (default=10)
    The number of base estimators in the ensemble.

max_samples : int or float, optional (default=1.0)
    The number of samples to draw from X to train each base estimator.
        - If int, then draw `max_samples` samples.
        - If float, then draw `max_samples * X.shape[0]` samples.

max_features : int or float, optional (default=1.0)
    The number of features to draw from X to train each base estimator.
        - If int, then draw `max_features` features.
        - If float, then draw `max_features * X.shape[1]` features.

bootstrap : boolean, optional (default=True)
    Whether samples are drawn with replacement.

bootstrap_features : boolean, optional (default=False)
    Whether features are drawn with replacement.

oob_score : bool
    Whether to use out-of-bag samples to estimate
    the generalization error.

warm_start : bool, optional (default=False)
    When set to True, reuse the solution of the previous call to fit
    and add more estimators to the ensemble, otherwise, just fit
    a whole new ensemble.

    .. versionadded:: 0.17
       *warm_start* constructor parameter.

n_jobs : int, optional (default=1)
    The number of jobs to run in parallel for both `fit` and `predict`.
    If -1, then the number of jobs is set to the number of cores.

random_state : int, RandomState instance or None, optional (default=None)
    If int, random_state is the seed used by the random number generator;
    If RandomState instance, random_state is the random number generator;
    If None, the random number generator is the RandomState instance used
    by `np.random`.

verbose : int, optional (default=0)
    Controls the verbosity of the building process.

**Attributes**

``base_estimator_`` : list of estimators
    The base estimator from which the ensemble is grown.

``estimators_`` : list of estimators
    The collection of fitted base estimators.

``estimators_samples_`` : list of arrays
    The subset of drawn samples (i.e., the in-bag samples) for each base
    estimator.

``estimators_features_`` : list of arrays
    The subset of drawn features for each base estimator.

``classes_`` : array of shape = [n_classes]
    The classes labels.

``n_classes_`` : int or list
    The number of classes.

``oob_score_`` : float
    Score of the training dataset obtained using an out-of-bag estimate.

``oob_decision_function_`` : array of shape = [n_samples, n_classes]
    Decision function computed with out-of-bag estimate on the training
    set. If n_estimators is small it might be possible that a data point
    was never left out during the bootstrap. In this case,
    `oob_decision_function_` might contain NaN.

**References**


.. [1] L. Breiman, "Pasting small votes for classification in large
       databases and on-line", Machine Learning, 36(1), 85-103, 1999.

.. [2] L. Breiman, "Bagging predictors", Machine Learning, 24(2), 123-140,
       1996.

.. [3] T. Ho, "The random subspace method for constructing decision
       forests", Pattern Analysis and Machine Intelligence, 20(8), 832-844,
       1998.

.. [4] G. Louppe and P. Geurts, "Ensembles on Random Patches", Machine
       Learning and Knowledge Discovery in Databases, 346-361, 2012.

Overrides: object.__init__

Overrides: Node.is_invertible

(inherited documentation)

Overrides: Node.is_trainable

Predict class for X.

This node has been automatically generated by wrapping the sklearn.ensemble.bagging.BaggingClassifier class from the sklearn library. The wrapped instance can be accessed through the scikits_alg attribute.

The predicted class of an input sample is computed as the class with the highest mean predicted probability. If base estimators do not implement a predict_proba method, then it resorts to voting.

Parameters

X : {array-like, sparse matrix} of shape = [n_samples, n_features]

The training input samples. Sparse matrices are accepted only if they are supported by the base estimator.

Returns

y : array of shape = [n_samples]

The predicted classes.

Overrides: ClassifierNode.label

Build a Bagging ensemble of estimators from the training set (X, y).

This node has been automatically generated by wrapping the sklearn.ensemble.bagging.BaggingClassifier class from the sklearn library. The wrapped instance can be accessed through the scikits_alg attribute.

Parameters

X : {array-like, sparse matrix} of shape = [n_samples, n_features]

The training input samples. Sparse matrices are accepted only if they are supported by the base estimator.

y : array-like, shape = [n_samples]

The target values (class labels in classification, real numbers in regression).

sample_weight : array-like, shape = [n_samples] or None

Sample weights. If None, then samples are equally weighted. Note that this is supported only if the base estimator supports sample weighting.

Returns

self : object

Returns self.

Overrides: Node.stop_training