crandas.crlearn

class crandas.crlearn.logistic_regression.LogisticRegression(penalty='l2', *, dual=False, tol=0.0001, C=1.0, fit_intercept=True, intercept_scaling=1, class_weight=None, random_state=None, solver='lbfgs', max_iter=10, multi_class='auto', verbose=0, warm_start=False, n_jobs=None, l1_ratio=None, classes=[], n_classes=2)

Bases: object

Logistic Regression Classifier Object with the same parameters as the Scikit learn Logistic Regression Class

See: https://github.com/scikit-learn/scikit-learn/blob/98cf537f5/sklearn/linear_model/_logistic.py#L783 for its parameters.

fit(X, y, sample_weight=None, max_iter=None, warm_start=None, **query_args)

Fit a Logistic Regression model on the data

Args - X (CDataFrame): predictor variables - y (CDataFrame): response variable (should have only 1 column) - sample_weight: array of weights assigned to individual sampled (Not yet supported) - max_iter: deviation from Scikit (see note below) - warm_start: deviation from Scikit (see note below)

if True: determines whether successive fits continue approximation from where it stopped else: indicates that each successive fit will start from scratch.

Returns - self

Note

Compared to Scikit learn we add the parameter max_iter and warm_start. Scikit learn treats max_iter and warm_start as object configurations which are set at construction and cannot be changed. We prefer to give the user the freedom of deviating form the global setting in successive fitting calls.

We rather use the corresponding class attributes as default values for each call to fit.

get_beta(**kwargs)

Get the fitted parameters (i.e. intercept_ and coef_ combined in 1 table named beta).

predict(X, decision_boundary=0.5, **query_args)

Make (binary) predictions on a dataset using a logistic regression model

Note: this returns binary predictions, not probabilities!

Args - X (CDataFrame): predictor variables - decision_boundary (float): number between 0 and 1; records with a probability below this value are classified as 0, greater than or equal to as 1

Returns - column consisting of the predicted probabilities (CDataFrame)

predict_proba(X, **query_args)

Make (probability) predictions on a dataset using a logistic regression model

Note: this returns probabilities, not binary predictions

Args - X (CDataFrame): predictor variables

Returns - column consisting of the predicted probabilities (CDataFrame)

class crandas.crlearn.logistic_regression.LogisticRegressionStateObject(reg_type, **kwargs)

Bases: StateObject

classmethod json_to_closed(deferred, json_answer)

Returns an instance of the class corresponding to to the provided JSON represention.

If the instance comes from a transaction, then deferred is the deferred object originally returned by vdl_query. This function should then check that the returned answer complies with the expected deferred. Otherwise, deferred is None.