sklearn.multioutput
.MultiOutputRegressor¶
-
class
sklearn.multioutput.
MultiOutputRegressor
(estimator, *, n_jobs=None)[source]¶ Multi target regression
This strategy consists of fitting one regressor per target. This is a simple strategy for extending regressors that do not natively support multi-target regression.
New in version 0.18.
- Parameters
- estimatorestimator object
- n_jobsint or None, optional (default=None)
The number of jobs to run in parallel for
fit
.None
means 1 unless in ajoblib.parallel_backend
context.-1
means using all processors. See Glossary for more details.When individual estimators are fast to train or predict using
n_jobs>1
can result in slower performance due to the overhead of spawning processes.Changed in version v0.20:
n_jobs
default changed from 1 to None
- Attributes
- estimators_list of
n_output
estimators Estimators used for predictions.
- estimators_list of
Examples
>>> import numpy as np >>> from sklearn.datasets import load_linnerud >>> from sklearn.multioutput import MultiOutputRegressor >>> from sklearn.linear_model import Ridge >>> X, y = load_linnerud(return_X_y=True) >>> clf = MultiOutputRegressor(Ridge(random_state=123)).fit(X, y) >>> clf.predict(X[[0]]) array([[176..., 35..., 57...]])
Methods
fit
(X, y[, sample_weight])Fit the model to data.
get_params
([deep])Get parameters for this estimator.
partial_fit
(X, y[, sample_weight])Incrementally fit the model to data.
predict
(X)Predict multi-output variable using a model
score
(X, y[, sample_weight])Return the coefficient of determination R^2 of the prediction.
set_params
(**params)Set the parameters of this estimator.
-
__init__
(estimator, *, n_jobs=None)[source]¶ Initialize self. See help(type(self)) for accurate signature.
-
fit
(X, y, sample_weight=None, **fit_params)[source]¶ Fit the model to data. Fit a separate model for each output variable.
- Parameters
- X(sparse) array-like, shape (n_samples, n_features)
Data.
- y(sparse) array-like, shape (n_samples, n_outputs)
Multi-output targets. An indicator matrix turns on multilabel estimation.
- sample_weightarray-like of shape (n_samples,), default=None
Sample weights. If None, then samples are equally weighted. Only supported if the underlying regressor supports sample weights.
- **fit_paramsdict of string -> object
Parameters passed to the
estimator.fit
method of each step.
- Returns
- selfobject
-
get_params
(deep=True)[source]¶ Get parameters for this estimator.
- Parameters
- deepbool, default=True
If True, will return the parameters for this estimator and contained subobjects that are estimators.
- Returns
- paramsmapping of string to any
Parameter names mapped to their values.
-
partial_fit
(X, y, sample_weight=None)[source]¶ Incrementally fit the model to data. Fit a separate model for each output variable.
- Parameters
- X(sparse) array-like, shape (n_samples, n_features)
Data.
- y(sparse) array-like, shape (n_samples, n_outputs)
Multi-output targets.
- sample_weightarray-like of shape (n_samples,), default=None
Sample weights. If None, then samples are equally weighted. Only supported if the underlying regressor supports sample weights.
- Returns
- selfobject
-
predict
(X)[source]¶ - Predict multi-output variable using a model
trained for each target variable.
- Parameters
- X(sparse) array-like, shape (n_samples, n_features)
Data.
- Returns
- y(sparse) array-like, shape (n_samples, n_outputs)
Multi-output targets predicted across multiple predictors. Note: Separate models are generated for each predictor.
-
score
(X, y, sample_weight=None)[source]¶ Return the coefficient of determination R^2 of the prediction.
The coefficient R^2 is defined as (1 - u/v), where u is the residual sum of squares ((y_true - y_pred) ** 2).sum() and v is the total sum of squares ((y_true - y_true.mean()) ** 2).sum(). The best possible score is 1.0 and it can be negative (because the model can be arbitrarily worse). A constant model that always predicts the expected value of y, disregarding the input features, would get a R^2 score of 0.0.
- Parameters
- Xarray-like of shape (n_samples, n_features)
Test samples. For some estimators this may be a precomputed kernel matrix or a list of generic objects instead, shape = (n_samples, n_samples_fitted), where n_samples_fitted is the number of samples used in the fitting for the estimator.
- yarray-like of shape (n_samples,) or (n_samples, n_outputs)
True values for X.
- sample_weightarray-like of shape (n_samples,), default=None
Sample weights.
- Returns
- scorefloat
R^2 of self.predict(X) wrt. y.
Notes
The R2 score used when calling
score
on a regressor usesmultioutput='uniform_average'
from version 0.23 to keep consistent with default value ofr2_score
. This influences thescore
method of all the multioutput regressors (except forMultiOutputRegressor
).
-
set_params
(**params)[source]¶ Set the parameters of this estimator.
The method works on simple estimators as well as on nested objects (such as pipelines). The latter have parameters of the form
<component>__<parameter>
so that it’s possible to update each component of a nested object.- Parameters
- **paramsdict
Estimator parameters.
- Returns
- selfobject
Estimator instance.