Python3 使用SVM--Lasso等,训练模型,画出auc曲线

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注意:roc_curve() 这个函数

来源于:sklearn.metrics.roc_curve

roc_curve(y_true, y_score, pos_label=None, sample_weight=None, drop_intermediate=True)注意它的参数:Parameters:y_true : array, shape = [n_samples]      True binary labels in range {0, 1} or {-1, 1}. If labels are not binary, pos_label should be explicitly given.y_score : array, shape = [n_samples]      Target scores, can either be probability estimates of the positive class, confidence values, or non-thresholded measure of decisions (as returned by “decision_function” on some classifiers).pos_label : int or str, default=None       Label considered as positive and others are considered negative. ...

注意第二个参数是:y_score,它可以是:对正例的概率估计值,置信度值,
决策值的非阈值测量(一些分类器中用decision_function来返回)

例如:

Model = classifier.fit(TrainX, Trainy)1.probas_ = Model.predict_proba(TestX)#一些分类器直接predict_proba,返回概率值predictions = Model.predict(TestX)#predict返回预测值fpr, tpr, thresholds = roc_curve(Testy,probas_[:,1],pos_label=1)2.probas_ = Model.decision_function(TestX)#返回
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