在进行多项式回归分析时,用python分别实现L1正则调优和L2正则调优
时间: 2024-03-28 12:41:50 浏览: 122
好的,针对您的问题,我可以给出以下的Python代码实现:
L1正则调优:
```python
from sklearn.linear_model import Lasso
from sklearn.preprocessing import PolynomialFeatures
from sklearn.pipeline import make_pipeline
from sklearn.model_selection import GridSearchCV
import numpy as np
# 构造数据
x = np.array([0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0])
y = np.array([0.1, 0.9, 2.8, 6.5, 12.4, 20.5, 30.8, 43.3, 58.0, 74.9])
# 构造管道
model = make_pipeline(PolynomialFeatures(degree=9), Lasso())
# 构造参数选项
param_grid = {'lasso__alpha': np.logspace(-5, 1, 50)}
# 执行交叉验证调优
grid = GridSearchCV(model, param_grid, cv=5, iid=False)
grid.fit(x[:, np.newaxis], y)
# 输出结果
print("最优参数:", grid.best_params_)
print("最优得分:", grid.best_score_)
```
L2正则调优:
```python
from sklearn.linear_model import Ridge
from sklearn.preprocessing import PolynomialFeatures
from sklearn.pipeline import make_pipeline
from sklearn.model_selection import GridSearchCV
import numpy as np
# 构造数据
x = np.array([0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0])
y = np.array([0.1, 0.9, 2.8, 6.5, 12.4, 20.5, 30.8, 43.3, 58.0, 74.9])
# 构造管道
model = make_pipeline(PolynomialFeatures(degree=9), Ridge())
# 构造参数选项
param_grid = {'ridge__alpha': np.logspace(-5, 1, 50)}
# 执行交叉验证调优
grid = GridSearchCV(model, param_grid, cv=5, iid=False)
grid.fit(x[:, np.newaxis], y)
# 输出结果
print("最优参数:", grid.best_params_)
print("最优得分:", grid.best_score_)
```
以上就是 L1正则调优 和 L2正则调优 的Python代码实现,希望能够帮助到您。
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