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added ridge regression
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commit
6fc134d96c
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@ -1,6 +1,7 @@
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import numpy as np
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import pandas as pd
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class RidgeRegression:
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def __init__(self, alpha:float=0.001, regularization_param:float=0.1, num_iterations:int=1000) -> None:
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self.alpha:float = alpha
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@ -8,8 +9,12 @@ class RidgeRegression:
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self.num_iterations:int = num_iterations
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self.theta:np.ndarray = None
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<<<<<<< HEAD
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def feature_scaling(self, X:np.ndarray) -> tuple[np.ndarray, np.ndarray, np.ndarray]:
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=======
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def feature_scaling(self, X):
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>>>>>>> d4fc2bf852ec4a023380f4ef367edefa88fd6881
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mean = np.mean(X, axis=0)
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std = np.std(X, axis=0)
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@ -19,7 +24,6 @@ class RidgeRegression:
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X_scaled = (X - mean) / std
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return X_scaled, mean, std
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def fit(self, X:np.ndarray, y:np.ndarray) -> None:
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X_scaled, mean, std = self.feature_scaling(X)
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m, n = X_scaled.shape
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@ -30,24 +34,30 @@ class RidgeRegression:
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error = predictions - y
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# computing gradient with L2 regularization
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gradient = (X_scaled.T.dot(error) + self.regularization_param * self.theta) / m
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gradient = (
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X_scaled.T.dot(error) + self.regularization_param * self.theta
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) / m
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self.theta -= self.alpha * gradient # updating weights
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def predict(self, X:np.ndarray) -> np.ndarray:
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X_scaled, _, _ = self.feature_scaling(X)
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return X_scaled.dot(self.theta)
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<<<<<<< HEAD
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def compute_cost(self, X:np.ndarray, y:np.ndarray) -> float:
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X_scaled, _, _ = self.feature_scaling(X)
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=======
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def compute_cost(self, X, y):
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X_scaled, _, _ = self.feature_scaling(X)
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>>>>>>> d4fc2bf852ec4a023380f4ef367edefa88fd6881
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m = len(y)
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predictions = X_scaled.dot(self.theta)
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cost = (1 / (2 * m)) * np.sum((predictions - y) ** 2) + (self.regularization_param / (2 * m)) * np.sum(self.theta**2)
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cost = (1 / (2 * m)) * np.sum((predictions - y) ** 2) + (
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self.regularization_param / (2 * m)
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) * np.sum(self.theta**2)
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return cost
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def mean_absolute_error(self, y_true:np.ndarray, y_pred:np.ndarray) -> float:
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return np.mean(np.abs(y_true - y_pred))
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@ -59,8 +69,13 @@ if __name__ == "__main__":
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y = df["ADR"].values
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y = (y - np.mean(y)) / np.std(y)
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<<<<<<< HEAD
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# added bias term to the feature matrix
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X = np.c_[np.ones(X.shape[0]), X]
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=======
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# Add bias term (intercept) to the feature matrix
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X = np.c_[np.ones(X.shape[0]), X]
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>>>>>>> d4fc2bf852ec4a023380f4ef367edefa88fd6881
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# initialize and train the ridge regression model
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model = RidgeRegression(alpha=0.01, regularization_param=0.1, num_iterations=1000)
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