generated from LufsX/Experiment-LogReg
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+45
-30
@@ -29,6 +29,51 @@ name = "章程鸿"
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import numpy as np
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import numpy as np
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from sklearn.preprocessing import MinMaxScaler
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from sklearn.preprocessing import MinMaxScaler
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from sklearn.model_selection import train_test_split
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from sklearn.model_selection import train_test_split
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def sigmoid(z):
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return 1.0 / (1 + np.exp(-z))
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def compute_gradient(X_batch, y_batch, weights, lambda_reg):
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z = np.dot(X_batch, weights)
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h = sigmoid(z)
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gradient = np.dot(X_batch.T, (h - y_batch)) / len(y_batch)
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gradient += (lambda_reg / len(y_batch)) * weights # L2正则化
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return gradient
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def train_logreg(X, y, learning_rate=0.001, iterations=10000, batch_size=64, lambda_reg=0.1):
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m, n = X.shape
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weights = np.random.randn(n) * np.sqrt(2. / n) # He初始化
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best_weights = weights.copy()
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best_accuracy = 0
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for _ in range(iterations):
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indices = np.random.permutation(m)
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X_shuffled = X[indices]
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y_shuffled = y[indices]
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for j in range(0, m, batch_size):
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X_batch = X_shuffled[j:j + batch_size]
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y_batch = y_shuffled[j:j + batch_size]
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gradient = compute_gradient(X_batch, y_batch, weights, lambda_reg)
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weights -= learning_rate * gradient
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# 计算训练集准确率
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train_accuracy = accuracy(X, y, weights)
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if train_accuracy > best_accuracy:
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best_accuracy = train_accuracy
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best_weights = weights.copy()
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# 动态调整学习率
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if _ % 100 == 0 and train_accuracy > 0.95: # 达到高准确率时减小学习率
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learning_rate *= 0.9
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return best_weights
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def predict_logreg(X, weights):
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z = np.dot(X, weights)
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h = sigmoid(z)
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return np.where(h >= 0.5, 1, 0)
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def load_data(filepath):
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def load_data(filepath):
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data, labels = [], []
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data, labels = [], []
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with open(filepath, 'r') as f:
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with open(filepath, 'r') as f:
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@@ -58,36 +103,6 @@ def load_data(filepath):
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return data, target_variable
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return data, target_variable
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def load_data(filepath):
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data, labels = [], []
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with open(filepath, 'r') as f:
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for line in f:
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line = line.strip().split()
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if len(line) >= 1 and line[-1].isdigit():
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line_data = [0 if x == '?' else float(x) for x in line[:-1]]
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data.append(line_data)
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labels.append(int(line[-1]))
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data = np.array(data)
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labels = np.array(labels)
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# 检查特征数量
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num_features = data.shape[1]
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print(f"特征数量: {num_features}")
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# 特征选择:去掉特征3(索引2)和特征24~28(索引23~26),确保索引有效
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indices_to_delete = [2] # 特征3
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if num_features > 24: # 确保特征数量足够
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indices_to_delete += list(range(24, 27)) # 特征24到27(索引23到26)
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# 删除特征
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data = np.delete(data, indices_to_delete, axis=1)
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# 将标签二分类化,特征23(索引22)取值2和3合并为0,其余为1
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target_variable = np.where((labels == 2) | (labels == 3), 0, 1)
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return data, target_variable
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# 其余代码保持不变
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# 其余代码保持不变
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