[英]How to plot ROC curves based on mean and standard deviation in python?
Here is an example from the sklearn website where you need to这是您需要的sklearn 网站的示例
Classification is used for validation of the model.分类用于模型的验证。
Separate training and testing dataset单独的训练和测试数据集
Apply CrossValidation on models对模型应用交叉验证
import numpy as np from sklearn import datasets # Import some data to play with iris = datasets.load_iris() X = iris.data y = iris.target X, y = X[y != 2], y[y != 2] n_samples, n_features = X.shape # Add noisy features random_state = np.random.RandomState(0) X = np.c_[X, random_state.randn(n_samples, 200 * n_features)] import matplotlib.pyplot as plt from sklearn import svm from sklearn.metrics import auc from sklearn.metrics import RocCurveDisplay from sklearn.model_selection import StratifiedKFold # Run classifier with cross-validation and plot ROC curves cv = StratifiedKFold(n_splits=6) classifier = svm.SVC(kernel="linear", probability=True, random_state=random_state) tprs = [] aucs = [] mean_fpr = np.linspace(0, 1, 100) fig, ax = plt.subplots() for i, (train, test) in enumerate(cv.split(X, y)): classifier.fit(X[train], y[train]) viz = RocCurveDisplay.from_estimator( classifier, X[test], y[test], name="ROC fold {}".format(i), alpha=0.3, lw=1, ax=ax, ) interp_tpr = np.interp(mean_fpr, viz.fpr, viz.tpr) interp_tpr[0] = 0.0 tprs.append(interp_tpr) aucs.append(viz.roc_auc) ax.plot([0, 1], [0, 1], linestyle="--", lw=2, color="r", label="Chance", alpha=0.8) mean_tpr = np.mean(tprs, axis=0) mean_tpr[-1] = 1.0 mean_auc = auc(mean_fpr, mean_tpr) std_auc = np.std(aucs) ax.plot( mean_fpr, mean_tpr, color="b", label=r"Mean ROC (AUC = %0.2f $\pm$ %0.2f)" % (mean_auc, std_auc), lw=2, alpha=0.8, ) std_tpr = np.std(tprs, axis=0) tprs_upper = np.minimum(mean_tpr + std_tpr, 1) tprs_lower = np.maximum(mean_tpr - std_tpr, 0) ax.fill_between( mean_fpr, tprs_lower, tprs_upper, color="grey", alpha=0.2, label=r"$\pm$ 1 std. dev.", ) ax.set( xlim=[-0.05, 1.05], ylim=[-0.05, 1.05], title="Receiver operating characteristic example", ) ax.legend(loc="lower right") plt.show()
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.