使用python调用sklearn库实现对乳腺癌数据的分类,采用逻辑回归分类方法,并计算以下性能评价指标:平均精确率、AUC,并绘制PR曲线与ROC曲线。
时间: 2024-02-27 18:59:26 浏览: 217
好的,我可以为您解答这个问题。
首先,我们需要加载乳腺癌数据集并进行预处理。代码如下:
``` python
from sklearn.datasets import load_breast_cancer
from sklearn.model_selection import train_test_split
from sklearn.preprocessing import StandardScaler
data = load_breast_cancer()
X, y = data.data, data.target
sc = StandardScaler()
X = sc.fit_transform(X)
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2, random_state=42)
```
接下来,我们需要使用逻辑回归模型进行训练和预测,计算平均精确率和AUC。代码如下:
``` python
from sklearn.linear_model import LogisticRegression
from sklearn.metrics import accuracy_score, precision_score, roc_auc_score, roc_curve, precision_recall_curve
import matplotlib.pyplot as plt
lr = LogisticRegression()
lr.fit(X_train, y_train)
y_pred = lr.predict(X_test)
accuracy = accuracy_score(y_test, y_pred)
precision = precision_score(y_test, y_pred)
y_proba = lr.predict_proba(X_test)[:, 1]
auc = roc_auc_score(y_test, y_proba)
print("Accuracy: {:.2f}%".format(accuracy * 100))
print("Precision: {:.2f}%".format(precision * 100))
print("AUC: {:.2f}%".format(auc * 100))
```
最后,我们可以绘制PR曲线和ROC曲线。代码如下:
``` python
fpr, tpr, thresholds = roc_curve(y_test, y_proba)
precision, recall, thresholds = precision_recall_curve(y_test, y_proba)
plt.plot(fpr, tpr, label="ROC curve")
plt.plot(recall, precision, label="PR curve")
plt.legend()
plt.show()
```
这样,我们就完成了对乳腺癌数据的分类,并计算了平均精确率、AUC,绘制了PR曲线和ROC曲线。
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