DocumentationClassesAdaBoostClassifier

Class: AdaBoostClassifier

An AdaBoost classifier.

An AdaBoost [1] classifier is a meta-estimator that begins by fitting a classifier on the original dataset and then fits additional copies of the classifier on the same dataset but where the weights of incorrectly classified instances are adjusted such that subsequent classifiers focus more on difficult cases.

This class implements the algorithm based on [2].

Read more in the User Guide.

Python Reference

Constructors

new AdaBoostClassifier()

new AdaBoostClassifier(opts?): AdaBoostClassifier

Parameters

ParameterTypeDescription
opts?object-
opts.algorithm?"SAMME" | "SAMME.R"If ‘SAMME.R’ then use the SAMME.R real boosting algorithm. estimator must support calculation of class probabilities. If ‘SAMME’ then use the SAMME discrete boosting algorithm. The SAMME.R algorithm typically converges faster than SAMME, achieving a lower test error with fewer boosting iterations.
opts.estimator?anyThe base estimator from which the boosted ensemble is built. Support for sample weighting is required, as well as proper classes_ and n_classes_ attributes. If undefined, then the base estimator is DecisionTreeClassifier initialized with max_depth=1.
opts.learning_rate?numberWeight applied to each classifier at each boosting iteration. A higher learning rate increases the contribution of each classifier. There is a trade-off between the learning_rate and n_estimators parameters. Values must be in the range (0.0, inf).
opts.n_estimators?numberThe maximum number of estimators at which boosting is terminated. In case of perfect fit, the learning procedure is stopped early. Values must be in the range \[1, inf).
opts.random_state?numberControls the random seed given at each estimator at each boosting iteration. Thus, it is only used when estimator exposes a random_state. Pass an int for reproducible output across multiple function calls. See Glossary.

Returns AdaBoostClassifier

Defined in generated/ensemble/AdaBoostClassifier.ts:27

Properties

PropertyTypeDefault valueDefined in
_isDisposedbooleanfalsegenerated/ensemble/AdaBoostClassifier.ts:25
_isInitializedbooleanfalsegenerated/ensemble/AdaBoostClassifier.ts:24
_pyPythonBridgeundefinedgenerated/ensemble/AdaBoostClassifier.ts:23
idstringundefinedgenerated/ensemble/AdaBoostClassifier.ts:20
optsanyundefinedgenerated/ensemble/AdaBoostClassifier.ts:21

Accessors

classes_

Get Signature

get classes_(): Promise<ArrayLike>

The classes labels.

Returns Promise<ArrayLike>

Defined in generated/ensemble/AdaBoostClassifier.ts:706


estimator_

Get Signature

get estimator_(): Promise<any>

The base estimator from which the ensemble is grown.

Returns Promise<any>

Defined in generated/ensemble/AdaBoostClassifier.ts:652


estimator_errors_

Get Signature

get estimator_errors_(): Promise<any>

Classification error for each estimator in the boosted ensemble.

Returns Promise<any>

Defined in generated/ensemble/AdaBoostClassifier.ts:787


estimator_weights_

Get Signature

get estimator_weights_(): Promise<any>

Weights for each estimator in the boosted ensemble.

Returns Promise<any>

Defined in generated/ensemble/AdaBoostClassifier.ts:760


estimators_

Get Signature

get estimators_(): Promise<any>

The collection of fitted sub-estimators.

Returns Promise<any>

Defined in generated/ensemble/AdaBoostClassifier.ts:679


feature_names_in_

Get Signature

get feature_names_in_(): Promise<ArrayLike>

Names of features seen during fit. Defined only when X has feature names that are all strings.

Returns Promise<ArrayLike>

Defined in generated/ensemble/AdaBoostClassifier.ts:841


n_classes_

Get Signature

get n_classes_(): Promise<number>

The number of classes.

Returns Promise<number>

Defined in generated/ensemble/AdaBoostClassifier.ts:733


n_features_in_

Get Signature

get n_features_in_(): Promise<number>

Number of features seen during fit.

Returns Promise<number>

Defined in generated/ensemble/AdaBoostClassifier.ts:814


py

Get Signature

get py(): PythonBridge

Returns PythonBridge

Set Signature

set py(pythonBridge): void

Parameters

ParameterType
pythonBridgePythonBridge

Returns void

Defined in generated/ensemble/AdaBoostClassifier.ts:63

Methods

decision_function()

decision_function(opts): Promise<any>

Compute the decision function of X.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLikeThe training input samples. Sparse matrix can be CSC, CSR, COO, DOK, or LIL. COO, DOK, and LIL are converted to CSR.

Returns Promise<any>

Defined in generated/ensemble/AdaBoostClassifier.ts:136


dispose()

dispose(): Promise<void>

Disposes of the underlying Python resources.

Once dispose() is called, the instance is no longer usable.

Returns Promise<void>

Defined in generated/ensemble/AdaBoostClassifier.ts:119


fit()

fit(opts): Promise<any>

Build a boosted classifier/regressor from the training set (X, y).

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?ArrayLikeSample weights. If undefined, the sample weights are initialized to 1 / n_samples.
opts.X?ArrayLikeThe training input samples. Sparse matrix can be CSC, CSR, COO, DOK, or LIL. COO, DOK, and LIL are converted to CSR.
opts.y?ArrayLikeThe target values.

Returns Promise<any>

Defined in generated/ensemble/AdaBoostClassifier.ts:172


get_metadata_routing()

get_metadata_routing(opts): Promise<any>

Raise NotImplementedError.

This estimator does not support metadata routing yet.

Parameters

ParameterType
optsobject

Returns Promise<any>

Defined in generated/ensemble/AdaBoostClassifier.ts:218


init()

init(py): Promise<void>

Initializes the underlying Python resources.

This instance is not usable until the Promise returned by init() resolves.

Parameters

ParameterType
pyPythonBridge

Returns Promise<void>

Defined in generated/ensemble/AdaBoostClassifier.ts:76


predict()

predict(opts): Promise<ArrayLike>

Predict classes for X.

The predicted class of an input sample is computed as the weighted mean prediction of the classifiers in the ensemble.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLikeThe training input samples. Sparse matrix can be CSC, CSR, COO, DOK, or LIL. COO, DOK, and LIL are converted to CSR.

Returns Promise<ArrayLike>

Defined in generated/ensemble/AdaBoostClassifier.ts:250


predict_log_proba()

predict_log_proba(opts): Promise<ArrayLike[]>

Predict class log-probabilities for X.

The predicted class log-probabilities of an input sample is computed as the weighted mean predicted class log-probabilities of the classifiers in the ensemble.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLikeThe training input samples. Sparse matrix can be CSC, CSR, COO, DOK, or LIL. COO, DOK, and LIL are converted to CSR.

Returns Promise<ArrayLike[]>

Defined in generated/ensemble/AdaBoostClassifier.ts:286


predict_proba()

predict_proba(opts): Promise<ArrayLike[]>

Predict class probabilities for X.

The predicted class probabilities of an input sample is computed as the weighted mean predicted class probabilities of the classifiers in the ensemble.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLikeThe training input samples. Sparse matrix can be CSC, CSR, COO, DOK, or LIL. COO, DOK, and LIL are converted to CSR.

Returns Promise<ArrayLike[]>

Defined in generated/ensemble/AdaBoostClassifier.ts:324


score()

score(opts): Promise<number>

Return the mean accuracy on the given test data and labels.

In multi-label classification, this is the subset accuracy which is a harsh metric since you require for each sample that each label set be correctly predicted.

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?ArrayLikeSample weights.
opts.X?ArrayLike[]Test samples.
opts.y?ArrayLikeTrue labels for X.

Returns Promise<number>

Defined in generated/ensemble/AdaBoostClassifier.ts:362


set_fit_request()

set_fit_request(opts): Promise<any>

Request metadata passed to the fit method.

Note that this method is only relevant if enable_metadata_routing=True (see sklearn.set_config). Please see User Guide on how the routing mechanism works.

The options for each parameter are:

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?string | booleanMetadata routing for sample_weight parameter in fit.

Returns Promise<any>

Defined in generated/ensemble/AdaBoostClassifier.ts:410


set_score_request()

set_score_request(opts): Promise<any>

Request metadata passed to the score method.

Note that this method is only relevant if enable_metadata_routing=True (see sklearn.set_config). Please see User Guide on how the routing mechanism works.

The options for each parameter are:

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?string | booleanMetadata routing for sample_weight parameter in score.

Returns Promise<any>

Defined in generated/ensemble/AdaBoostClassifier.ts:450


staged_decision_function()

staged_decision_function(opts): Promise<any[]>

Compute decision function of X for each boosting iteration.

This method allows monitoring (i.e. determine error on testing set) after each boosting iteration.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLikeThe training input samples. Sparse matrix can be CSC, CSR, COO, DOK, or LIL. COO, DOK, and LIL are converted to CSR.

Returns Promise<any[]>

Defined in generated/ensemble/AdaBoostClassifier.ts:488


staged_predict()

staged_predict(opts): Promise<any[]>

Return staged predictions for X.

The predicted class of an input sample is computed as the weighted mean prediction of the classifiers in the ensemble.

This generator method yields the ensemble prediction after each iteration of boosting and therefore allows monitoring, such as to determine the prediction on a test set after each boost.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLike[]The input samples. Sparse matrix can be CSC, CSR, COO, DOK, or LIL. COO, DOK, and LIL are converted to CSR.

Returns Promise<any[]>

Defined in generated/ensemble/AdaBoostClassifier.ts:528


staged_predict_proba()

staged_predict_proba(opts): Promise<any[]>

Predict class probabilities for X.

The predicted class probabilities of an input sample is computed as the weighted mean predicted class probabilities of the classifiers in the ensemble.

This generator method yields the ensemble predicted class probabilities after each iteration of boosting and therefore allows monitoring, such as to determine the predicted class probabilities on a test set after each boost.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLikeThe training input samples. Sparse matrix can be CSC, CSR, COO, DOK, or LIL. COO, DOK, and LIL are converted to CSR.

Returns Promise<any[]>

Defined in generated/ensemble/AdaBoostClassifier.ts:568


staged_score()

staged_score(opts): Promise<number>

Return staged scores for X, y.

This generator method yields the ensemble score after each iteration of boosting and therefore allows monitoring, such as to determine the score on a test set after each boost.

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?ArrayLikeSample weights.
opts.X?ArrayLikeThe training input samples. Sparse matrix can be CSC, CSR, COO, DOK, or LIL. COO, DOK, and LIL are converted to CSR.
opts.y?ArrayLikeLabels for X.

Returns Promise<number>

Defined in generated/ensemble/AdaBoostClassifier.ts:606