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BinarySegmentation

BinarySegmentation

class BinarySegmentation(threshold, min_cp_distance=0, max_iter=10000)[source]

Binary segmentation change point detector.

This method finds change points by fitting piecewise constant functions to a timeseries. Change points are selected according to the CUMSUM statistic.

Parameters:
thresholdfloat

Threshold for the CUMSUM statistic. Change points that do not increase the CUMSUM statistic above this threshold are ignored.

min_cp_distanceint

Minimum distance between change points.

max_iterint

Maximum number of interactions before the found change points are returned.

Attributes:
is_fitted

Whether fit has been called.

Notes

This is based on the implementation of binary segmentation described in [1].

References

[1]

Fryzlewicz, Piotr. “WILD BINARY SEGMENTATION FOR MULTIPLE CHANGE-POINT DETECTION.” The Annals of Statistics, vol. 42, no. 6, 2014, pp. 2243-81. JSTOR, http://www.jstor.org/stable/43556493. Accessed 4 July 2024.

Examples

>>> import pandas as pd
>>> from sktime.detection.bs import BinarySegmentation
>>> model = BinarySegmentation(threshold=1)
>>> X = pd.Series([1, 1, 1, 1, 5, 5, 5, 5])
>>> model.fit_predict(X)
   ilocs
0      3
>>> X = pd.Series([1.1, 1.3, -1.4, -1.4, 5.5, 5.6])
>>> model.fit_predict(X)
   ilocs
0      1
1      3

Methods

change_points_to_segments(y_sparse[, start, end])

Convert an series of change point indexes to segments.

check_is_fitted([method_name])

Check if the estimator has been fitted.

clone()

Obtain a clone of the object with same hyper-parameters and config.

clone_tags(estimator[, tag_names])

Clone tags from another object as dynamic override.

create_test_instance([parameter_set])

Construct an instance of the class, using first test parameter set.

create_test_instances_and_names([parameter_set])

Create list of all test instances and a list of names for them.

dense_to_sparse(y_dense)

Convert the dense output from an detector to a sparse format.

fit(X[, y])

Fit to training data.

fit_predict(X[, y])

Fit to data, then predict it.

fit_transform(X[, y])

Fit to data, then transform it.

get_class_tag(tag_name[, tag_value_default])

Get class tag value from class, with tag level inheritance from parents.

get_class_tags()

Get class tags from class, with tag level inheritance from parent classes.

get_config()

Get config flags for self.

get_fitted_params([deep])

Get fitted parameters.

get_param_defaults()

Get object's parameter defaults.

get_param_names([sort])

Get object's parameter names.

get_params([deep])

Get a dict of parameters values for this object.

get_tag(tag_name[, tag_value_default, ...])

Get tag value from instance, with tag level inheritance and overrides.

get_tags()

Get tags from instance, with tag level inheritance and overrides.

get_test_params([parameter_set])

Return testing parameter settings for the estimator.

is_composite()

Check if the object is composed of other BaseObjects.

load_from_path(serial)

Load object from file location.

load_from_serial(serial)

Load object from serialized memory container.

predict(X)

Create labels on test/deployment data.

predict_points(X)

Predict changepoints/anomalies on test/deployment data.

predict_scores(X)

Return scores for predicted labels on test/deployment data.

predict_segments(X)

Predict segments on test/deployment data.

reset()

Reset the object to a clean post-init state.

save([path, serialization_format])

Save serialized self to bytes-like object or to (.zip) file.

segments_to_change_points(y_sparse)

Convert segments to change points.

set_config(**config_dict)

Set config flags to given values.

set_params(**params)

Set the parameters of this object.

set_random_state([random_state, deep, ...])

Set random_state pseudo-random seed parameters for self.

set_tags(**tag_dict)

Set instance level tag overrides to given values.

sparse_to_dense(y_sparse, index)

Convert the sparse output from an detector to a dense format.

transform(X)

Create labels on test/deployment data.

transform_scores(X)

Return scores for predicted labels on test/deployment data.

update(X[, y])

Update model with new data and optional ground truth labels.

update_predict(X[, y])

Update model with new data and create labels for it.