Stacked Classifier¶
-
class
deslib.static.stacked.
StackedClassifier
(pool_classifiers=None, meta_classifier=None, passthrough=False, random_state=None, n_jobs=-1)[source]¶ A Stacking classifier.
Parameters: - pool_classifiers : list of classifiers (Default = None)
The generated_pool of classifiers trained for the corresponding classification problem. Each base classifiers should support the method “predict” and “predict_proba”. If None, then the pool of classifiers is a bagging classifier.
- meta_classifier : object or None, optional (default=None)
Classifier model used to aggregate the output of the base classifiers. If None, a
LogisticRegression
classifier is used.- 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.
- passthrough : bool (default=False)
When False, only the predictions of estimators will be used as training data for the meta-classifier. When True, the meta-classifier is trained on the predictions as well as the original training data.
- n_jobs : int, default=-1
The number of parallel jobs to run. None means 1 unless in a joblib.parallel_backend context. -1 means using all processors. Doesn’t affect fit method.
References
Wolpert, David H. “Stacked generalization.” Neural networks 5, no. 2 (1992): 241-259.
Kuncheva, Ludmila I. Combining pattern classifiers: methods and algorithms. John Wiley & Sons, 2004.
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fit
(X, y)[source]¶ Fit the model by training a meta-classifier on the outputs of the base classifiers
Parameters: - X : array of shape (n_samples, n_features)
Data used to fit the model.
- y : array of shape (n_samples)
class labels of each example in X.
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predict
(X)[source]¶ Predict the label of each sample in X and returns the predicted label.
Parameters: - X : array of shape (n_samples, n_features)
The data to be classified
Returns: - predicted_labels : array of shape (n_samples)
Predicted class for each sample in X.
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predict_proba
(X)[source]¶ Predict the label of each sample in X and returns the predicted label.
Parameters: - X : array of shape (n_samples, n_features)
The data to be classified
Returns: - predicted_labels : array of shape (n_samples)
Predicted class for each sample in X.
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score
(X, y, sample_weight=None)[source]¶ 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: - X : array-like of shape (n_samples, n_features)
Test samples.
- y : array-like of shape (n_samples,) or (n_samples, n_outputs)
True labels for X.
- sample_weight : array-like of shape (n_samples,), default=None
Sample weights.
Returns: - score : float
Mean accuracy of
self.predict(X)
wrt. y.