72 lines
2.4 KiB
Python
72 lines
2.4 KiB
Python
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from sklearn.linear_model import LassoCV
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from sklearn.ensemble import RandomForestRegressor
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from sklearn.feature_selection import RFE
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from sklearn.preprocessing import MinMaxScaler
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import numpy as np
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import pandas as pd
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def rank_to_dict(ranks, names):
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ranks = np.abs(ranks)
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minmax = MinMaxScaler()
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ranks = minmax.fit_transform(np.array(ranks).reshape(14, 1)).ravel()
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ranks = map(lambda x: round(x, 2), ranks)
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return dict(zip(names, ranks))
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np.random.seed(0)
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size = 750
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X = np.random.uniform(0, 1, (size, 14))
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Y = (10 * np.sin(np.pi * X[:, 0] * X[:, 1]) + 20 * (X[:, 2] - .5) ** 2 +
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10 * X[:, 3] + 5 * X[:, 4] ** 5 + np.random.normal(0, 1, size))
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X[:, 10:] = X[:, :4] + np.random.normal(0, .025, (size, 4))
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lasso_cv = LassoCV(alphas=np.linspace(0.001, 1, 100), cv=5)
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lasso_cv.fit(X, Y)
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rf = RandomForestRegressor(n_estimators=100)
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rfe = RFE(estimator=rf, n_features_to_select=1, step=1)
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rfe.fit(X, Y)
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# названия признаков
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names = ["x%s" % i for i in range(1, 15)]
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# Stable Randomized Lasso Simulation
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n_resampling = 200
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rlasso_coefs = np.zeros((X.shape[1], n_resampling))
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for i in range(n_resampling):
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Y_permuted = np.random.permutation(Y)
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rlasso = LassoCV(alphas=np.linspace(0.001, 1, 100), cv=5)
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rlasso.fit(X, Y_permuted)
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rlasso_coefs[:, i] = rlasso.coef_
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rlasso_scores = np.std(rlasso_coefs, axis=1)
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# словарь для ранжирования
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ranks = {"Lasso": rank_to_dict(lasso_cv.coef_, names),
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"RFE": rank_to_dict(rfe.ranking_, names),
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"RandomizedLassoSim": rank_to_dict(rlasso_scores, names)}
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mean = {}
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for method, values in ranks.items():
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for feature, score in values.items():
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# Если элемента с текущим ключом в mean нет - добавляем
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if feature not in mean:
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mean[feature] = 0
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# Суммируем значения по каждому ключу-имени признака
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mean[feature] += score
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df_ranks = pd.DataFrame(ranks)
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# Выводим ранжирование
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print("ПО КАЖДОМУ МЕТОДУ:")
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print(df_ranks)
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# Находим среднее по каждому признаку
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for feature, score in mean.items():
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mean[feature] = round(score / len(ranks), 2)
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# Отсортированные средние значени
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mean = sorted(mean.items(), key=lambda x: x[1], reverse=True)
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print("СРЕДНИЕ")
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print(mean)
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