python - 返回 adaboost python 中使用的模型

Question

在 svm 上应用 adaboost 后，我​​想知道 adaboost 算法中使用的模型（它们的参数）。

ada=AdaBoostClassifier(n_estimators=10, base_estimator=SVC(probability=True)) 
ada.fit(x_train,y_train)

我怎样才能找到 adaboost 中使用的模型。谢谢

Answer 1

您的对象的estimators_字段AdaBoostClassifier包含您的每个模型。查看这些模型的详细信息将取决于用于构建它们的内容。因此，例如，您可能需要在下面的示例中查看如何查找如何获取 a 的信息DecisionTreeClassifier：

>>> from sklearn.datasets import load_iris
>>> from sklearn.ensemble import AdaBoostClassifier
>>> 
>>> iris = load_iris()
>>> clf = AdaBoostClassifier(n_estimators=2)
>>> clf.fit(iris.data, iris.target)
AdaBoostClassifier(algorithm='SAMME.R',
          base_estimator=DecisionTreeClassifier(compute_importances=None, criterion='gini',
            max_depth=1, max_features=None, min_density=None,
            min_samples_leaf=1, min_samples_split=2, random_state=None,
            splitter='best'),
          learning_rate=1.0, n_estimators=2, random_state=None)
>>> clf.estimators_
[DecisionTreeClassifier(compute_importances=None, criterion='gini',
            max_depth=1, max_features=None, min_density=None,
            min_samples_leaf=1, min_samples_split=2, random_state=None,
            splitter='best'), DecisionTreeClassifier(compute_importances=None, criterion='gini',
            max_depth=1, max_features=None, min_density=None,
            min_samples_leaf=1, min_samples_split=2, random_state=None,
            splitter='best')]
>>> 
>>> #first model
... clf.estimators_[0]
DecisionTreeClassifier(compute_importances=None, criterion='gini',
            max_depth=1, max_features=None, min_density=None,
            min_samples_leaf=1, min_samples_split=2, random_state=None,
            splitter='best')
>>> #second model
... clf.estimators_[1]
DecisionTreeClassifier(compute_importances=None, criterion='gini',
            max_depth=1, max_features=None, min_density=None,
            min_samples_leaf=1, min_samples_split=2, random_state=None,
            splitter='best')