lightgbm.DaskLGBMRegressor¶

class
lightgbm.
DaskLGBMRegressor
(boosting_type='gbdt', num_leaves=31, max_depth= 1, learning_rate=0.1, n_estimators=100, subsample_for_bin=200000, objective=None, class_weight=None, min_split_gain=0.0, min_child_weight=0.001, min_child_samples=20, subsample=1.0, subsample_freq=0, colsample_bytree=1.0, reg_alpha=0.0, reg_lambda=0.0, random_state=None, n_jobs= 1, silent=True, importance_type='split', client=None, **kwargs)[source]¶ Bases:
lightgbm.sklearn.LGBMRegressor
,lightgbm.dask._DaskLGBMModel
Distributed version of lightgbm.LGBMRegressor.

__init__
(boosting_type='gbdt', num_leaves=31, max_depth= 1, learning_rate=0.1, n_estimators=100, subsample_for_bin=200000, objective=None, class_weight=None, min_split_gain=0.0, min_child_weight=0.001, min_child_samples=20, subsample=1.0, subsample_freq=0, colsample_bytree=1.0, reg_alpha=0.0, reg_lambda=0.0, random_state=None, n_jobs= 1, silent=True, importance_type='split', client=None, **kwargs)[source]¶ Construct a gradient boosting model.
 Parameters
boosting_type (string, optional (default='gbdt')) – ‘gbdt’, traditional Gradient Boosting Decision Tree. ‘dart’, Dropouts meet Multiple Additive Regression Trees. ‘goss’, Gradientbased OneSide Sampling. ‘rf’, Random Forest.
num_leaves (int, optional (default=31)) – Maximum tree leaves for base learners.
max_depth (int, optional (default=1)) – Maximum tree depth for base learners, <=0 means no limit.
learning_rate (float, optional (default=0.1)) – Boosting learning rate. You can use
callbacks
parameter offit
method to shrink/adapt learning rate in training usingreset_parameter
callback. Note, that this will ignore thelearning_rate
argument in training.n_estimators (int, optional (default=100)) – Number of boosted trees to fit.
subsample_for_bin (int, optional (default=200000)) – Number of samples for constructing bins.
objective (string, callable or None, optional (default=None)) – Specify the learning task and the corresponding learning objective or a custom objective function to be used (see note below). Default: ‘regression’ for LGBMRegressor, ‘binary’ or ‘multiclass’ for LGBMClassifier, ‘lambdarank’ for LGBMRanker.
class_weight (dict, 'balanced' or None, optional (default=None)) – Weights associated with classes in the form
{class_label: weight}
. Use this parameter only for multiclass classification task; for binary classification task you may useis_unbalance
orscale_pos_weight
parameters. Note, that the usage of all these parameters will result in poor estimates of the individual class probabilities. You may want to consider performing probability calibration (https://scikitlearn.org/stable/modules/calibration.html) of your model. The ‘balanced’ mode uses the values of y to automatically adjust weights inversely proportional to class frequencies in the input data asn_samples / (n_classes * np.bincount(y))
. If None, all classes are supposed to have weight one. Note, that these weights will be multiplied withsample_weight
(passed through thefit
method) ifsample_weight
is specified.min_split_gain (float, optional (default=0.)) – Minimum loss reduction required to make a further partition on a leaf node of the tree.
min_child_weight (float, optional (default=1e3)) – Minimum sum of instance weight (hessian) needed in a child (leaf).
min_child_samples (int, optional (default=20)) – Minimum number of data needed in a child (leaf).
subsample (float, optional (default=1.)) – Subsample ratio of the training instance.
subsample_freq (int, optional (default=0)) – Frequence of subsample, <=0 means no enable.
colsample_bytree (float, optional (default=1.)) – Subsample ratio of columns when constructing each tree.
reg_alpha (float, optional (default=0.)) – L1 regularization term on weights.
reg_lambda (float, optional (default=0.)) – L2 regularization term on weights.
random_state (int, RandomState object or None, optional (default=None)) – Random number seed. If int, this number is used to seed the C++ code. If RandomState object (numpy), a random integer is picked based on its state to seed the C++ code. If None, default seeds in C++ code are used.
n_jobs (int, optional (default=1)) – Number of parallel threads.
silent (bool, optional (default=True)) – Whether to print messages while running boosting.
importance_type (string, optional (default='split')) – The type of feature importance to be filled into
feature_importances_
. If ‘split’, result contains numbers of times the feature is used in a model. If ‘gain’, result contains total gains of splits which use the feature.client (dask.distributed.Client or None, optional (default=None)) – Dask client. If
None
,distributed.default_client()
will be used at runtime. The Dask client used by this class will not be saved if the model object is pickled.**kwargs –
Other parameters for the model. Check http://lightgbm.readthedocs.io/en/latest/Parameters.html for more parameters.
Warning
**kwargs is not supported in sklearn, it may cause unexpected issues.
Methods
__init__
([boosting_type, num_leaves, …])Construct a gradient boosting model.
fit
(X, y[, sample_weight, init_score])Build a gradient boosting model from the training set (X, y).
get_params
([deep])Get parameters for this estimator.
predict
(X, **kwargs)Return the predicted value for each sample.
set_params
(**params)Set the parameters of this estimator.
to_local
()Create regular version of lightgbm.LGBMRegressor from the distributed version.
Attributes
The best iteration of fitted model if
early_stopping_rounds
has been specified.The best score of fitted model.
The underlying Booster of this model.
Dask client.
The evaluation results if
early_stopping_rounds
has been specified.The feature importances (the higher, the more important).
The names of features.
The number of features of fitted model.
The number of features of fitted model.
The concrete objective used while fitting this model.

property
best_iteration_
¶ The best iteration of fitted model if
early_stopping_rounds
has been specified. Type
int
orNone

property
best_score_
¶ The best score of fitted model.
 Type
dict
orNone

property
client_
¶ Dask client.
This property can be passed in the constructor or updated with
model.set_params(client=client)
. Type
dask.distributed.Client

property
evals_result_
¶ The evaluation results if
early_stopping_rounds
has been specified. Type
dict
orNone

property
feature_importances_
¶ The feature importances (the higher, the more important).
Note
importance_type
attribute is passed to the function to configure the type of importance values to be extracted. Type
array
of shape = [n_features]

property
feature_name_
¶ The names of features.
 Type
array
of shape = [n_features]

fit
(X, y, sample_weight=None, init_score=None, **kwargs)[source]¶ Build a gradient boosting model from the training set (X, y).
 Parameters
X (Dask Array or Dask DataFrame of shape = [n_samples, n_features]) – Input feature matrix.
y (Dask Array, Dask DataFrame or Dask Series of shape = [n_samples]) – The target values (class labels in classification, real numbers in regression).
sample_weight (Dask Array, Dask DataFrame, Dask Series of shape = [n_samples] or None, optional (default=None)) – Weights of training data.
init_score (Dask Array, Dask DataFrame, Dask Series of shape = [n_samples] or None, optional (default=None)) – Init score of training data.
verbose (bool or int, optional (default=True)) –
Requires at least one evaluation data. If True, the eval metric on the eval set is printed at each boosting stage. If int, the eval metric on the eval set is printed at every
verbose
boosting stage. The last boosting stage or the boosting stage found by usingearly_stopping_rounds
is also printed.Example
With
verbose
= 4 and at least one item ineval_set
, an evaluation metric is printed every 4 (instead of 1) boosting stages.feature_name (list of strings or 'auto', optional (default='auto')) – Feature names. If ‘auto’ and data is pandas DataFrame, data columns names are used.
categorical_feature (list of strings or int, or 'auto', optional (default='auto')) – Categorical features. If list of int, interpreted as indices. If list of strings, interpreted as feature names (need to specify
feature_name
as well). If ‘auto’ and data is pandas DataFrame, pandas unordered categorical columns are used. All values in categorical features should be less than int32 max value (2147483647). Large values could be memory consuming. Consider using consecutive integers starting from zero. All negative values in categorical features will be treated as missing values. The output cannot be monotonically constrained with respect to a categorical feature.**kwargs – Other parameters passed through to
LGBMRegressor.fit()
.

get_params
(deep=True)¶ Get parameters for this estimator.
 Parameters
deep (bool, optional (default=True)) – If True, will return the parameters for this estimator and contained subobjects that are estimators.
 Returns
params – Parameter names mapped to their values.
 Return type
dict

property
n_features_
¶ The number of features of fitted model.
 Type
int

property
n_features_in_
¶ The number of features of fitted model.
 Type
int

property
objective_
¶ The concrete objective used while fitting this model.
 Type
string
orcallable

predict
(X, **kwargs)[source]¶ Return the predicted value for each sample.
 Parameters
X (Dask Array or Dask DataFrame of shape = [n_samples, n_features]) – Input features matrix.
raw_score (bool, optional (default=False)) – Whether to predict raw scores.
start_iteration (int, optional (default=0)) – Start index of the iteration to predict. If <= 0, starts from the first iteration.
num_iteration (int or None, optional (default=None)) – Total number of iterations used in the prediction. If None, if the best iteration exists and start_iteration <= 0, the best iteration is used; otherwise, all iterations from
start_iteration
are used (no limits). If <= 0, all iterations fromstart_iteration
are used (no limits).pred_leaf (bool, optional (default=False)) – Whether to predict leaf index.
pred_contrib (bool, optional (default=False)) –
Whether to predict feature contributions.
Note
If you want to get more explanations for your model’s predictions using SHAP values, like SHAP interaction values, you can install the shap package (https://github.com/slundberg/shap). Note that unlike the shap package, with
pred_contrib
we return a matrix with an extra column, where the last column is the expected value.**kwargs – Other parameters for the prediction.
 Returns
predicted_result (Dask Array of shape = [n_samples]) – The predicted values.
X_leaves (Dask Array of shape = [n_samples, n_trees]) – If
pred_leaf=True
, the predicted leaf of every tree for each sample.X_SHAP_values (Dask Array of shape = [n_samples, n_features + 1]) – If
pred_contrib=True
, the feature contributions for each sample.

set_params
(**params)¶ Set the parameters of this estimator.
 Parameters
**params – Parameter names with their new values.
 Returns
self – Returns self.
 Return type
object
