特徵選擇

特徵選擇 1. 移除低方差 方差計算公式：html 離散型： D(X)=E{[X-E(X)]^2}=E(X^2) - [ E(X)]^2python ∑(X−avg(X))2N #sklearn 實現 # http://scikit-learn.org/stable/modules/generated/sklearn.feature_selection.VarianceThreshold.html

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