标签:port process bre 分类 orm targe == 自己的 ace
1.逻辑回归是怎么防止过拟合的?为什么正则化可以防止过拟合?(大家用自己的话介绍下)
逻辑回归在算法层面是通过正则化来防止过拟合的,因为正则化是通过约束参数的范数使其不要太大,所以能够防止过拟合。
2.用logiftic回归来进行实践操作,数据不限。
import pandas as pd import numpy as np from sklearn.linear_model import LogisticRegression from sklearn.model_selection import train_test_split from sklearn.preprocessing import StandardScaler from sklearn.metrics import classification_report from sklearn.metrics import mean_squared_error # 逻辑回归 def logistic(): # 分类 column = [‘数据编号‘, ‘属性1‘, ‘属性2‘, ‘属性3‘, ‘属性4‘, ‘属性5‘, ‘属性6‘, ‘属性7‘, ‘属性8‘, ‘属性9‘, ‘类别‘] # 读取数据 data = pd.read_csv(‘C:\\Users\\86186\\Desktop\\大三下\\机器学习\\breast-cancer-wisconsin.csv‘, names=column) # 缺失值处理 data = data.replace(to_replace=‘?‘, value=np.nan) data = data.dropna() # 数据分割 x_train, x_test, y_train, y_test = train_test_split(data[column[1:10]], data[column[10]], test_size=0.3) # 特征值和目标值进行标准化处理(分别处理) std = StandardScaler() x_train = std.fit_transform(x_train) x_test = std.transform(x_test) # 逻辑回归预测 lg = LogisticRegression() lg.fit(x_train, y_train) print(lg.coef_) lg_predict = lg.predict(x_test) print(‘准确率:‘, lg.score(x_test, y_test)) print(‘召回率:‘, classification_report(y_test, lg_predict, labels=[2, 4], target_names=[‘良性‘, ‘恶性‘])) if __name__ == ‘__main__‘: logistic()
实验结果如下
标签:port process bre 分类 orm targe == 自己的 ace
原文地址:https://www.cnblogs.com/fzybk/p/12785752.html