722 lines
30 KiB
Python
722 lines
30 KiB
Python
"""Partial dependence plots for regression and classification models."""
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# Authors: Peter Prettenhofer
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# Trevor Stephens
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# Nicolas Hug
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# License: BSD 3 clause
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from collections.abc import Iterable
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import numpy as np
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from scipy import sparse
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from scipy.stats.mstats import mquantiles
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from ..base import is_classifier, is_regressor
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from ..ensemble import RandomForestRegressor
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from ..ensemble._gb import BaseGradientBoosting
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from ..ensemble._hist_gradient_boosting.gradient_boosting import (
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BaseHistGradientBoosting,
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)
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from ..exceptions import NotFittedError
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from ..tree import DecisionTreeRegressor
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from ..utils import Bunch, _safe_indexing, check_array
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from ..utils._indexing import _determine_key_type, _get_column_indices, _safe_assign
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from ..utils._optional_dependencies import check_matplotlib_support # noqa
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from ..utils._param_validation import (
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HasMethods,
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Integral,
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Interval,
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StrOptions,
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validate_params,
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)
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from ..utils.extmath import cartesian
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from ..utils.validation import _check_sample_weight, check_is_fitted
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from ._pd_utils import _check_feature_names, _get_feature_index
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__all__ = [
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"partial_dependence",
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]
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def _grid_from_X(X, percentiles, is_categorical, grid_resolution):
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"""Generate a grid of points based on the percentiles of X.
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The grid is a cartesian product between the columns of ``values``. The
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ith column of ``values`` consists in ``grid_resolution`` equally-spaced
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points between the percentiles of the jth column of X.
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If ``grid_resolution`` is bigger than the number of unique values in the
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j-th column of X or if the feature is a categorical feature (by inspecting
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`is_categorical`) , then those unique values will be used instead.
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Parameters
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----------
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X : array-like of shape (n_samples, n_target_features)
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The data.
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percentiles : tuple of float
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The percentiles which are used to construct the extreme values of
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the grid. Must be in [0, 1].
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is_categorical : list of bool
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For each feature, tells whether it is categorical or not. If a feature
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is categorical, then the values used will be the unique ones
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(i.e. categories) instead of the percentiles.
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grid_resolution : int
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The number of equally spaced points to be placed on the grid for each
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feature.
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Returns
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-------
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grid : ndarray of shape (n_points, n_target_features)
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A value for each feature at each point in the grid. ``n_points`` is
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always ``<= grid_resolution ** X.shape[1]``.
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values : list of 1d ndarrays
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The values with which the grid has been created. The size of each
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array ``values[j]`` is either ``grid_resolution``, or the number of
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unique values in ``X[:, j]``, whichever is smaller.
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"""
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if not isinstance(percentiles, Iterable) or len(percentiles) != 2:
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raise ValueError("'percentiles' must be a sequence of 2 elements.")
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if not all(0 <= x <= 1 for x in percentiles):
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raise ValueError("'percentiles' values must be in [0, 1].")
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if percentiles[0] >= percentiles[1]:
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raise ValueError("percentiles[0] must be strictly less than percentiles[1].")
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if grid_resolution <= 1:
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raise ValueError("'grid_resolution' must be strictly greater than 1.")
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values = []
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# TODO: we should handle missing values (i.e. `np.nan`) specifically and store them
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# in a different Bunch attribute.
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for feature, is_cat in enumerate(is_categorical):
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try:
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uniques = np.unique(_safe_indexing(X, feature, axis=1))
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except TypeError as exc:
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# `np.unique` will fail in the presence of `np.nan` and `str` categories
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# due to sorting. Temporary, we reraise an error explaining the problem.
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raise ValueError(
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f"The column #{feature} contains mixed data types. Finding unique "
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"categories fail due to sorting. It usually means that the column "
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"contains `np.nan` values together with `str` categories. Such use "
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"case is not yet supported in scikit-learn."
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) from exc
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if is_cat or uniques.shape[0] < grid_resolution:
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# Use the unique values either because:
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# - feature has low resolution use unique values
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# - feature is categorical
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axis = uniques
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else:
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# create axis based on percentiles and grid resolution
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emp_percentiles = mquantiles(
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_safe_indexing(X, feature, axis=1), prob=percentiles, axis=0
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)
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if np.allclose(emp_percentiles[0], emp_percentiles[1]):
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raise ValueError(
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"percentiles are too close to each other, "
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"unable to build the grid. Please choose percentiles "
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"that are further apart."
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)
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axis = np.linspace(
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emp_percentiles[0],
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emp_percentiles[1],
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num=grid_resolution,
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endpoint=True,
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)
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values.append(axis)
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return cartesian(values), values
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def _partial_dependence_recursion(est, grid, features):
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"""Calculate partial dependence via the recursion method.
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The recursion method is in particular enabled for tree-based estimators.
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For each `grid` value, a weighted tree traversal is performed: if a split node
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involves an input feature of interest, the corresponding left or right branch
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is followed; otherwise both branches are followed, each branch being weighted
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by the fraction of training samples that entered that branch. Finally, the
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partial dependence is given by a weighted average of all the visited leaves
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values.
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This method is more efficient in terms of speed than the `'brute'` method
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(:func:`~sklearn.inspection._partial_dependence._partial_dependence_brute`).
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However, here, the partial dependence computation is done explicitly with the
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`X` used during training of `est`.
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Parameters
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----------
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est : BaseEstimator
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A fitted estimator object implementing :term:`predict` or
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:term:`decision_function`. Multioutput-multiclass classifiers are not
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supported. Note that `'recursion'` is only supported for some tree-based
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estimators (namely
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:class:`~sklearn.ensemble.GradientBoostingClassifier`,
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:class:`~sklearn.ensemble.GradientBoostingRegressor`,
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:class:`~sklearn.ensemble.HistGradientBoostingClassifier`,
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:class:`~sklearn.ensemble.HistGradientBoostingRegressor`,
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:class:`~sklearn.tree.DecisionTreeRegressor`,
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:class:`~sklearn.ensemble.RandomForestRegressor`,
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).
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grid : array-like of shape (n_points, n_target_features)
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The grid of feature values for which the partial dependence is calculated.
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Note that `n_points` is the number of points in the grid and `n_target_features`
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is the number of features you are doing partial dependence at.
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features : array-like of {int, str}
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The feature (e.g. `[0]`) or pair of interacting features
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(e.g. `[(0, 1)]`) for which the partial dependency should be computed.
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Returns
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-------
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averaged_predictions : array-like of shape (n_targets, n_points)
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The averaged predictions for the given `grid` of features values.
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Note that `n_targets` is the number of targets (e.g. 1 for binary
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classification, `n_tasks` for multi-output regression, and `n_classes` for
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multiclass classification) and `n_points` is the number of points in the `grid`.
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"""
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averaged_predictions = est._compute_partial_dependence_recursion(grid, features)
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if averaged_predictions.ndim == 1:
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# reshape to (1, n_points) for consistency with
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# _partial_dependence_brute
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averaged_predictions = averaged_predictions.reshape(1, -1)
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return averaged_predictions
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def _partial_dependence_brute(
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est, grid, features, X, response_method, sample_weight=None
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):
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"""Calculate partial dependence via the brute force method.
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The brute method explicitly averages the predictions of an estimator over a
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grid of feature values.
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For each `grid` value, all the samples from `X` have their variables of
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interest replaced by that specific `grid` value. The predictions are then made
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and averaged across the samples.
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This method is slower than the `'recursion'`
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(:func:`~sklearn.inspection._partial_dependence._partial_dependence_recursion`)
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version for estimators with this second option. However, with the `'brute'`
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force method, the average will be done with the given `X` and not the `X`
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used during training, as it is done in the `'recursion'` version. Therefore
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the average can always accept `sample_weight` (even when the estimator was
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fitted without).
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Parameters
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----------
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est : BaseEstimator
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A fitted estimator object implementing :term:`predict`,
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:term:`predict_proba`, or :term:`decision_function`.
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Multioutput-multiclass classifiers are not supported.
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grid : array-like of shape (n_points, n_target_features)
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The grid of feature values for which the partial dependence is calculated.
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Note that `n_points` is the number of points in the grid and `n_target_features`
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is the number of features you are doing partial dependence at.
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features : array-like of {int, str}
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The feature (e.g. `[0]`) or pair of interacting features
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(e.g. `[(0, 1)]`) for which the partial dependency should be computed.
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X : array-like of shape (n_samples, n_features)
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`X` is used to generate values for the complement features. That is, for
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each value in `grid`, the method will average the prediction of each
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sample from `X` having that grid value for `features`.
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response_method : {'auto', 'predict_proba', 'decision_function'}, \
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default='auto'
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Specifies whether to use :term:`predict_proba` or
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:term:`decision_function` as the target response. For regressors
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this parameter is ignored and the response is always the output of
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:term:`predict`. By default, :term:`predict_proba` is tried first
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and we revert to :term:`decision_function` if it doesn't exist.
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sample_weight : array-like of shape (n_samples,), default=None
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Sample weights are used to calculate weighted means when averaging the
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model output. If `None`, then samples are equally weighted. Note that
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`sample_weight` does not change the individual predictions.
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Returns
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-------
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averaged_predictions : array-like of shape (n_targets, n_points)
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The averaged predictions for the given `grid` of features values.
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Note that `n_targets` is the number of targets (e.g. 1 for binary
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classification, `n_tasks` for multi-output regression, and `n_classes` for
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multiclass classification) and `n_points` is the number of points in the `grid`.
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predictions : array-like
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The predictions for the given `grid` of features values over the samples
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from `X`. For non-multioutput regression and binary classification the
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shape is `(n_instances, n_points)` and for multi-output regression and
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multiclass classification the shape is `(n_targets, n_instances, n_points)`,
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where `n_targets` is the number of targets (`n_tasks` for multi-output
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regression, and `n_classes` for multiclass classification), `n_instances`
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is the number of instances in `X`, and `n_points` is the number of points
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in the `grid`.
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"""
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predictions = []
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averaged_predictions = []
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# define the prediction_method (predict, predict_proba, decision_function).
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if is_regressor(est):
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prediction_method = est.predict
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else:
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predict_proba = getattr(est, "predict_proba", None)
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decision_function = getattr(est, "decision_function", None)
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if response_method == "auto":
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# try predict_proba, then decision_function if it doesn't exist
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prediction_method = predict_proba or decision_function
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else:
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prediction_method = (
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predict_proba
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if response_method == "predict_proba"
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else decision_function
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)
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if prediction_method is None:
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if response_method == "auto":
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raise ValueError(
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"The estimator has no predict_proba and no "
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"decision_function method."
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)
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elif response_method == "predict_proba":
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raise ValueError("The estimator has no predict_proba method.")
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else:
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raise ValueError("The estimator has no decision_function method.")
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X_eval = X.copy()
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for new_values in grid:
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for i, variable in enumerate(features):
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_safe_assign(X_eval, new_values[i], column_indexer=variable)
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try:
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# Note: predictions is of shape
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# (n_points,) for non-multioutput regressors
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# (n_points, n_tasks) for multioutput regressors
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# (n_points, 1) for the regressors in cross_decomposition (I think)
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# (n_points, 2) for binary classification
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# (n_points, n_classes) for multiclass classification
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pred = prediction_method(X_eval)
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predictions.append(pred)
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# average over samples
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averaged_predictions.append(np.average(pred, axis=0, weights=sample_weight))
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except NotFittedError as e:
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raise ValueError("'estimator' parameter must be a fitted estimator") from e
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n_samples = X.shape[0]
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# reshape to (n_targets, n_instances, n_points) where n_targets is:
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# - 1 for non-multioutput regression and binary classification (shape is
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# already correct in those cases)
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# - n_tasks for multi-output regression
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# - n_classes for multiclass classification.
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predictions = np.array(predictions).T
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if is_regressor(est) and predictions.ndim == 2:
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# non-multioutput regression, shape is (n_instances, n_points,)
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predictions = predictions.reshape(n_samples, -1)
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elif is_classifier(est) and predictions.shape[0] == 2:
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# Binary classification, shape is (2, n_instances, n_points).
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# we output the effect of **positive** class
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predictions = predictions[1]
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predictions = predictions.reshape(n_samples, -1)
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# reshape averaged_predictions to (n_targets, n_points) where n_targets is:
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# - 1 for non-multioutput regression and binary classification (shape is
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# already correct in those cases)
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# - n_tasks for multi-output regression
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# - n_classes for multiclass classification.
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averaged_predictions = np.array(averaged_predictions).T
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if is_regressor(est) and averaged_predictions.ndim == 1:
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# non-multioutput regression, shape is (n_points,)
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averaged_predictions = averaged_predictions.reshape(1, -1)
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elif is_classifier(est) and averaged_predictions.shape[0] == 2:
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# Binary classification, shape is (2, n_points).
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# we output the effect of **positive** class
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averaged_predictions = averaged_predictions[1]
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averaged_predictions = averaged_predictions.reshape(1, -1)
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return averaged_predictions, predictions
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@validate_params(
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{
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"estimator": [
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HasMethods(["fit", "predict"]),
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HasMethods(["fit", "predict_proba"]),
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HasMethods(["fit", "decision_function"]),
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],
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"X": ["array-like", "sparse matrix"],
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"features": ["array-like", Integral, str],
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"sample_weight": ["array-like", None],
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"categorical_features": ["array-like", None],
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"feature_names": ["array-like", None],
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"response_method": [StrOptions({"auto", "predict_proba", "decision_function"})],
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"percentiles": [tuple],
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"grid_resolution": [Interval(Integral, 1, None, closed="left")],
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"method": [StrOptions({"auto", "recursion", "brute"})],
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"kind": [StrOptions({"average", "individual", "both"})],
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},
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prefer_skip_nested_validation=True,
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)
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def partial_dependence(
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estimator,
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X,
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features,
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*,
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sample_weight=None,
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categorical_features=None,
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feature_names=None,
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response_method="auto",
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percentiles=(0.05, 0.95),
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grid_resolution=100,
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method="auto",
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kind="average",
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):
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"""Partial dependence of ``features``.
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Partial dependence of a feature (or a set of features) corresponds to
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the average response of an estimator for each possible value of the
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feature.
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Read more in the :ref:`User Guide <partial_dependence>`.
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.. warning::
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For :class:`~sklearn.ensemble.GradientBoostingClassifier` and
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:class:`~sklearn.ensemble.GradientBoostingRegressor`, the
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`'recursion'` method (used by default) will not account for the `init`
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predictor of the boosting process. In practice, this will produce
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the same values as `'brute'` up to a constant offset in the target
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response, provided that `init` is a constant estimator (which is the
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default). However, if `init` is not a constant estimator, the
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partial dependence values are incorrect for `'recursion'` because the
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offset will be sample-dependent. It is preferable to use the `'brute'`
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method. Note that this only applies to
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:class:`~sklearn.ensemble.GradientBoostingClassifier` and
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:class:`~sklearn.ensemble.GradientBoostingRegressor`, not to
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:class:`~sklearn.ensemble.HistGradientBoostingClassifier` and
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:class:`~sklearn.ensemble.HistGradientBoostingRegressor`.
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Parameters
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----------
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estimator : BaseEstimator
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A fitted estimator object implementing :term:`predict`,
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:term:`predict_proba`, or :term:`decision_function`.
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Multioutput-multiclass classifiers are not supported.
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X : {array-like, sparse matrix or dataframe} of shape (n_samples, n_features)
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``X`` is used to generate a grid of values for the target
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``features`` (where the partial dependence will be evaluated), and
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also to generate values for the complement features when the
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`method` is 'brute'.
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features : array-like of {int, str, bool} or int or str
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The feature (e.g. `[0]`) or pair of interacting features
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(e.g. `[(0, 1)]`) for which the partial dependency should be computed.
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sample_weight : array-like of shape (n_samples,), default=None
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Sample weights are used to calculate weighted means when averaging the
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model output. If `None`, then samples are equally weighted. If
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`sample_weight` is not `None`, then `method` will be set to `'brute'`.
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Note that `sample_weight` is ignored for `kind='individual'`.
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.. versionadded:: 1.3
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categorical_features : array-like of shape (n_features,) or shape \
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(n_categorical_features,), dtype={bool, int, str}, default=None
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Indicates the categorical features.
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- `None`: no feature will be considered categorical;
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- boolean array-like: boolean mask of shape `(n_features,)`
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indicating which features are categorical. Thus, this array has
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the same shape has `X.shape[1]`;
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- integer or string array-like: integer indices or strings
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indicating categorical features.
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.. versionadded:: 1.2
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feature_names : array-like of shape (n_features,), dtype=str, default=None
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Name of each feature; `feature_names[i]` holds the name of the feature
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with index `i`.
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By default, the name of the feature corresponds to their numerical
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index for NumPy array and their column name for pandas dataframe.
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.. versionadded:: 1.2
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response_method : {'auto', 'predict_proba', 'decision_function'}, \
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default='auto'
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Specifies whether to use :term:`predict_proba` or
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:term:`decision_function` as the target response. For regressors
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this parameter is ignored and the response is always the output of
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:term:`predict`. By default, :term:`predict_proba` is tried first
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and we revert to :term:`decision_function` if it doesn't exist. If
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``method`` is 'recursion', the response is always the output of
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:term:`decision_function`.
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percentiles : tuple of float, default=(0.05, 0.95)
|
|
The lower and upper percentile used to create the extreme values
|
|
for the grid. Must be in [0, 1].
|
|
|
|
grid_resolution : int, default=100
|
|
The number of equally spaced points on the grid, for each target
|
|
feature.
|
|
|
|
method : {'auto', 'recursion', 'brute'}, default='auto'
|
|
The method used to calculate the averaged predictions:
|
|
|
|
- `'recursion'` is only supported for some tree-based estimators
|
|
(namely
|
|
:class:`~sklearn.ensemble.GradientBoostingClassifier`,
|
|
:class:`~sklearn.ensemble.GradientBoostingRegressor`,
|
|
:class:`~sklearn.ensemble.HistGradientBoostingClassifier`,
|
|
:class:`~sklearn.ensemble.HistGradientBoostingRegressor`,
|
|
:class:`~sklearn.tree.DecisionTreeRegressor`,
|
|
:class:`~sklearn.ensemble.RandomForestRegressor`,
|
|
) when `kind='average'`.
|
|
This is more efficient in terms of speed.
|
|
With this method, the target response of a
|
|
classifier is always the decision function, not the predicted
|
|
probabilities. Since the `'recursion'` method implicitly computes
|
|
the average of the Individual Conditional Expectation (ICE) by
|
|
design, it is not compatible with ICE and thus `kind` must be
|
|
`'average'`.
|
|
|
|
- `'brute'` is supported for any estimator, but is more
|
|
computationally intensive.
|
|
|
|
- `'auto'`: the `'recursion'` is used for estimators that support it,
|
|
and `'brute'` is used otherwise. If `sample_weight` is not `None`,
|
|
then `'brute'` is used regardless of the estimator.
|
|
|
|
Please see :ref:`this note <pdp_method_differences>` for
|
|
differences between the `'brute'` and `'recursion'` method.
|
|
|
|
kind : {'average', 'individual', 'both'}, default='average'
|
|
Whether to return the partial dependence averaged across all the
|
|
samples in the dataset or one value per sample or both.
|
|
See Returns below.
|
|
|
|
Note that the fast `method='recursion'` option is only available for
|
|
`kind='average'` and `sample_weights=None`. Computing individual
|
|
dependencies and doing weighted averages requires using the slower
|
|
`method='brute'`.
|
|
|
|
.. versionadded:: 0.24
|
|
|
|
Returns
|
|
-------
|
|
predictions : :class:`~sklearn.utils.Bunch`
|
|
Dictionary-like object, with the following attributes.
|
|
|
|
individual : ndarray of shape (n_outputs, n_instances, \
|
|
len(values[0]), len(values[1]), ...)
|
|
The predictions for all the points in the grid for all
|
|
samples in X. This is also known as Individual
|
|
Conditional Expectation (ICE).
|
|
Only available when `kind='individual'` or `kind='both'`.
|
|
|
|
average : ndarray of shape (n_outputs, len(values[0]), \
|
|
len(values[1]), ...)
|
|
The predictions for all the points in the grid, averaged
|
|
over all samples in X (or over the training data if
|
|
`method` is 'recursion').
|
|
Only available when `kind='average'` or `kind='both'`.
|
|
|
|
grid_values : seq of 1d ndarrays
|
|
The values with which the grid has been created. The generated
|
|
grid is a cartesian product of the arrays in `grid_values` where
|
|
`len(grid_values) == len(features)`. The size of each array
|
|
`grid_values[j]` is either `grid_resolution`, or the number of
|
|
unique values in `X[:, j]`, whichever is smaller.
|
|
|
|
.. versionadded:: 1.3
|
|
|
|
`n_outputs` corresponds to the number of classes in a multi-class
|
|
setting, or to the number of tasks for multi-output regression.
|
|
For classical regression and binary classification `n_outputs==1`.
|
|
`n_values_feature_j` corresponds to the size `grid_values[j]`.
|
|
|
|
See Also
|
|
--------
|
|
PartialDependenceDisplay.from_estimator : Plot Partial Dependence.
|
|
PartialDependenceDisplay : Partial Dependence visualization.
|
|
|
|
Examples
|
|
--------
|
|
>>> X = [[0, 0, 2], [1, 0, 0]]
|
|
>>> y = [0, 1]
|
|
>>> from sklearn.ensemble import GradientBoostingClassifier
|
|
>>> gb = GradientBoostingClassifier(random_state=0).fit(X, y)
|
|
>>> partial_dependence(gb, features=[0], X=X, percentiles=(0, 1),
|
|
... grid_resolution=2) # doctest: +SKIP
|
|
(array([[-4.52..., 4.52...]]), [array([ 0., 1.])])
|
|
"""
|
|
check_is_fitted(estimator)
|
|
|
|
if not (is_classifier(estimator) or is_regressor(estimator)):
|
|
raise ValueError("'estimator' must be a fitted regressor or classifier.")
|
|
|
|
if is_classifier(estimator) and isinstance(estimator.classes_[0], np.ndarray):
|
|
raise ValueError("Multiclass-multioutput estimators are not supported")
|
|
|
|
# Use check_array only on lists and other non-array-likes / sparse. Do not
|
|
# convert DataFrame into a NumPy array.
|
|
if not (hasattr(X, "__array__") or sparse.issparse(X)):
|
|
X = check_array(X, force_all_finite="allow-nan", dtype=object)
|
|
|
|
if is_regressor(estimator) and response_method != "auto":
|
|
raise ValueError(
|
|
"The response_method parameter is ignored for regressors and "
|
|
"must be 'auto'."
|
|
)
|
|
|
|
if kind != "average":
|
|
if method == "recursion":
|
|
raise ValueError(
|
|
"The 'recursion' method only applies when 'kind' is set to 'average'"
|
|
)
|
|
method = "brute"
|
|
|
|
if method == "recursion" and sample_weight is not None:
|
|
raise ValueError(
|
|
"The 'recursion' method can only be applied when sample_weight is None."
|
|
)
|
|
|
|
if method == "auto":
|
|
if sample_weight is not None:
|
|
method = "brute"
|
|
elif isinstance(estimator, BaseGradientBoosting) and estimator.init is None:
|
|
method = "recursion"
|
|
elif isinstance(
|
|
estimator,
|
|
(BaseHistGradientBoosting, DecisionTreeRegressor, RandomForestRegressor),
|
|
):
|
|
method = "recursion"
|
|
else:
|
|
method = "brute"
|
|
|
|
if method == "recursion":
|
|
if not isinstance(
|
|
estimator,
|
|
(
|
|
BaseGradientBoosting,
|
|
BaseHistGradientBoosting,
|
|
DecisionTreeRegressor,
|
|
RandomForestRegressor,
|
|
),
|
|
):
|
|
supported_classes_recursion = (
|
|
"GradientBoostingClassifier",
|
|
"GradientBoostingRegressor",
|
|
"HistGradientBoostingClassifier",
|
|
"HistGradientBoostingRegressor",
|
|
"HistGradientBoostingRegressor",
|
|
"DecisionTreeRegressor",
|
|
"RandomForestRegressor",
|
|
)
|
|
raise ValueError(
|
|
"Only the following estimators support the 'recursion' "
|
|
"method: {}. Try using method='brute'.".format(
|
|
", ".join(supported_classes_recursion)
|
|
)
|
|
)
|
|
if response_method == "auto":
|
|
response_method = "decision_function"
|
|
|
|
if response_method != "decision_function":
|
|
raise ValueError(
|
|
"With the 'recursion' method, the response_method must be "
|
|
"'decision_function'. Got {}.".format(response_method)
|
|
)
|
|
|
|
if sample_weight is not None:
|
|
sample_weight = _check_sample_weight(sample_weight, X)
|
|
|
|
if _determine_key_type(features, accept_slice=False) == "int":
|
|
# _get_column_indices() supports negative indexing. Here, we limit
|
|
# the indexing to be positive. The upper bound will be checked
|
|
# by _get_column_indices()
|
|
if np.any(np.less(features, 0)):
|
|
raise ValueError("all features must be in [0, {}]".format(X.shape[1] - 1))
|
|
|
|
features_indices = np.asarray(
|
|
_get_column_indices(X, features), dtype=np.intp, order="C"
|
|
).ravel()
|
|
|
|
feature_names = _check_feature_names(X, feature_names)
|
|
|
|
n_features = X.shape[1]
|
|
if categorical_features is None:
|
|
is_categorical = [False] * len(features_indices)
|
|
else:
|
|
categorical_features = np.asarray(categorical_features)
|
|
if categorical_features.dtype.kind == "b":
|
|
# categorical features provided as a list of boolean
|
|
if categorical_features.size != n_features:
|
|
raise ValueError(
|
|
"When `categorical_features` is a boolean array-like, "
|
|
"the array should be of shape (n_features,). Got "
|
|
f"{categorical_features.size} elements while `X` contains "
|
|
f"{n_features} features."
|
|
)
|
|
is_categorical = [categorical_features[idx] for idx in features_indices]
|
|
elif categorical_features.dtype.kind in ("i", "O", "U"):
|
|
# categorical features provided as a list of indices or feature names
|
|
categorical_features_idx = [
|
|
_get_feature_index(cat, feature_names=feature_names)
|
|
for cat in categorical_features
|
|
]
|
|
is_categorical = [
|
|
idx in categorical_features_idx for idx in features_indices
|
|
]
|
|
else:
|
|
raise ValueError(
|
|
"Expected `categorical_features` to be an array-like of boolean,"
|
|
f" integer, or string. Got {categorical_features.dtype} instead."
|
|
)
|
|
|
|
grid, values = _grid_from_X(
|
|
_safe_indexing(X, features_indices, axis=1),
|
|
percentiles,
|
|
is_categorical,
|
|
grid_resolution,
|
|
)
|
|
|
|
if method == "brute":
|
|
averaged_predictions, predictions = _partial_dependence_brute(
|
|
estimator, grid, features_indices, X, response_method, sample_weight
|
|
)
|
|
|
|
# reshape predictions to
|
|
# (n_outputs, n_instances, n_values_feature_0, n_values_feature_1, ...)
|
|
predictions = predictions.reshape(
|
|
-1, X.shape[0], *[val.shape[0] for val in values]
|
|
)
|
|
else:
|
|
averaged_predictions = _partial_dependence_recursion(
|
|
estimator, grid, features_indices
|
|
)
|
|
|
|
# reshape averaged_predictions to
|
|
# (n_outputs, n_values_feature_0, n_values_feature_1, ...)
|
|
averaged_predictions = averaged_predictions.reshape(
|
|
-1, *[val.shape[0] for val in values]
|
|
)
|
|
pdp_results = Bunch(grid_values=values)
|
|
|
|
if kind == "average":
|
|
pdp_results["average"] = averaged_predictions
|
|
elif kind == "individual":
|
|
pdp_results["individual"] = predictions
|
|
else: # kind='both'
|
|
pdp_results["average"] = averaged_predictions
|
|
pdp_results["individual"] = predictions
|
|
|
|
return pdp_results
|