liaosw97 Scikit-learn 机器学习指南
数据预处理
管道操作(Pipeline)
from sklearn.pipeline import Pipeline
from sklearn.impute import SimpleImputer
from sklearn.preprocessing import StandardScaler
from sklearn.ensemble import RandomForestClassifier
pipeline = Pipeline([
('imputer', SimpleImputer(strategy='median')),
('scaler', StandardScaler()),
('classifier', RandomForestClassifier(n_estimators=100))
])
模型训练
交叉验证最佳实践
from sklearn.model_selection import cross_val_score
scores = cross_val_score(
pipeline, X, y,
cv=5, # 5折交叉验证
scoring='accuracy'
)
print(f"平均准确率: {scores.mean():.2f} ± {scores.std():.2f}")