Univariate feature selector with configurable strategy.
Read more in the :ref:`User Guide <univariate_feature_selection>`.
Parameters ---------- score_func : callable Function taking two arrays X and y, and returning a pair of arrays (scores, pvalues). For modes 'percentile' or 'kbest' it can return a single array scores.
mode : 'percentile', 'k_best', 'fpr', 'fdr', 'fwe'
Feature selection mode.
param : float or int depending on the feature selection mode Parameter of the corresponding mode.
Attributes ---------- scores_ : array-like of shape (n_features,) Scores of features.
pvalues_ : array-like of shape (n_features,) p-values of feature scores, None if `score_func` returned scores only.
Examples -------- >>> from sklearn.datasets import load_breast_cancer >>> from sklearn.feature_selection import GenericUnivariateSelect, chi2 >>> X, y = load_breast_cancer(return_X_y=True) >>> X.shape (569, 30) >>> transformer = GenericUnivariateSelect(chi2, mode='k_best', param=20) >>> X_new = transformer.fit_transform(X, y) >>> X_new.shape (569, 20)
See also -------- f_classif: ANOVA F-value between label/feature for classification tasks. mutual_info_classif: Mutual information for a discrete target. chi2: Chi-squared stats of non-negative features for classification tasks. f_regression: F-value between label/feature for regression tasks. mutual_info_regression: Mutual information for a continuous target. SelectPercentile: Select features based on percentile of the highest scores. SelectKBest: Select features based on the k highest scores. SelectFpr: Select features based on a false positive rate test. SelectFdr: Select features based on an estimated false discovery rate. SelectFwe: Select features based on family-wise error rate.