注意:roc_curve() 這個函數
來源于:sklearn.metrics.roc_curve
roc_curve(y_true, y_score, pos_label=None, sample_weight=None, drop_intermediate=True)
注意它的參數:
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.
...
注意第二個參數是:y_score,它可以是:對正例的機率估計值,置信度值,
決策值的非門檻值測量(一些分類器中用decision_function來傳回)
例如:
Model = classifier.fit(TrainX, Trainy)
probas_ = Model.predict_proba(TestX)
#一些分類器直接predict_proba,傳回機率值
predictions = Model.predict(TestX)
#predict傳回預測值
fpr, tpr, thresholds = roc_curve(Testy,probas_[:,],pos_label=)
probas_ = Model.decision_function(TestX)
#傳回