Changelog#
Unreleased#
0.10.4 (20-09-2025)#
Efficiency Changed to Cython implementation for the loss functions and impurity measures of
CSLogitClassifier,CSBoostClassifier,CSTreeClassifier, andCSForestClassifier. This improves the training time and memory efficiency of these models significantly. Training time speedups observed were up to 300x forCSTreeClassifierandCSForestClassifier, 30x forCSLogitClassifier, and 1.5x forCSBoostClassifierdepending on the dataset size and parameters.API Change Changed arguments to
CSTreeClassifier,CSForestClassifier, andCSBaggingClassifierto be in line with scikit-learn’s decision tree and ensemble models.API Change
CSForestClassifier, andCSBaggingClassifierno longer support stacking combination method. UseStackingClassifierinstead for stacking.API Change Extracted the construction of the cost matrix into a separate class
CostMatrixaway fromMetricto allow reusing the cost matrix in custom metrics.API Change
ProfLogitClassifierno longer uses the EMPC metric by default. Users now need to explicitely pass a loss to the model.API Change
CSLogitClassifierno longer accepts any callable as loss function. Users now need to pass aMetricinstance for a custom loss function.Feature
savings_scoreandexpected_savings_scorenow accept two more baseline options ‘one’ and ‘zero’ to always predict the positive and negative class, respectively.Feature Metrics with with the
Savingsstrategy now also accepts baseline options likesavings_scoreandexpected_savings_score.Enhancement Models which use a
Metricinstance as their loss function with theCostorSavingsstrategy as their loss function now are pickleable. TheMaxProfitstrategy will be updated to be pickleable in a future release.Enhancement Models which use a
Metricinstance as their loss function can now request arguments necessary for the metric to be passed during the fit method through Metadata Routing.Fix Fix
CSLogitClassifiernot properly calculating gradient penalty.Fix Fix default values not being properly when using aliases in
CostMatrix.Fix Fix
Metricthrowing errors when certain terms cancelled out.
0.9.0 (15-06-2025)#
Feature Added
optimal_thresholdandoptimal_ratemethods to calculate the optimal threshold(s) and optimal predicted positive rate for a given metric. This is useful for determining the best decision threshold and predicted positive rate for a cost-sensitive or value-driven model.Feature
CSTreeClassifier,CSForestClassifier, andCSBaggingClassifiercan now take aMetricinstance as their criterion to optimize.Feature
CSThresholdClassifiercan now take aMetricinstance to choose the optimal decision threshold.Feature
RobustCSClassifiercan now take estimators with aMetricinstance as the loss function or criterion.RobustCSClassifierwill treat any cost marked as outlier sensitive. This can be done by using themark_outlier_sensitivemethod.Feature Allow savings metrics to be used in
CSBoostClassifierandCSLogitClassifieras the objective function. Internally, the expected cost loss is used to train the model, since the expected savings score is just a transformation of the expected cost loss.API Change kind argument to
Metrichas been replaced by strategy. TheMetricclass now takes aMetricStrategyinstance. This change allows for more flexibility in defining the metric strategy. The currently available strategies are:Fix Fix error when importing Empulse without any optional dependencies installed.
Fix Fix
CSLogitClassifiernot properly using the gradient when using a custom loss function fromMetric.Fix Fix models throwing errors when differently shaped costs are passed to the fit or predict method.
Fix Fix sympy distribution parameters not being properly translated to scipy distribution parameters when using the
MaxProfitstrategy (formerly kind=’max profit’) with the quasi monte-carlo integration method.
0.8.0 (01-06-2025)#
Feature
CSBoostClassifier,CSLogitClassifier, andProfLogitClassifiercan now take aMetricinstance as their loss function. Internally, the metric instance is converted to the appropriate loss function for the model. For more information, read the User Guide.Feature Type hints are now available for all functions and classes.
Enhancement Add support for more than one stochastic variable when building maximum profit metrics with
MetricEnhancement Allow
Metricto be used as a context manager. This ensures the metric is always built after defining the cost-benefit elements.Fix Fix datasets not properly being packaged together with the package
Fix Fix
RobustCSClassifierwhen array-like parameters are passed to fit method.Fix Fix boosting models being biased towards the positive class.
0.7.0 (05-02-2025)#
Major Feature Add
CSTreeClassifier,CSForestClassifier, andCSBaggingClassifierto support cost-sensitive decision tree and ensemble modelsEnhancement Add support for scikit-learn 1.5.2 (previously Empulse only supported scikit-learn 1.6.0 and above).
API Change Removed the
emp_scoreandempfunctions from themetricsmodule. Use theMetricclass instead to define custom expected maximum profit measures. For more information, read the User Guide.API Change Removed numba as a dependency for Empulse. This will reduce the installation time and the size of the package.
Fix Fix
Metricwhen defining stochastic variable with fixed values.Fix Fix
Metricwhen stochastic variable has infinite bounds.Fix Fix
CSThresholdClassifierwhen costs of predicting positive and negative classes are equal.Fix Fix documentation linking issues to sklearn
0.6.0 (28-01-2025)#
Major Feature Add
Metricto easily build your own value-driven and cost-sensitive metricsFeature Add support for LightGBM and Catboost models in
CSBoostClassifierandB2BoostClassifierAPI Change
make_objective_churnandmake_objective_acquisitionnow take amodelargument to calculate the objective for either XGBoost, LightGBM or Catboost models.API Change XGBoost is now an optional dependency together with LightGBM and Catboost. To install the package with XGBoost, LightGBM and Catboost support, use the following command:
pip install empulse[optional]API Change Renamed
y_pred_baselineandy_proba_baselinetobaselineinsavings_scoreandexpected_savings_score. It now accepts the following arguments:If
'zero_one', the baseline model is a naive model that predicts all zeros or all ones depending on which is better.If
'prior', the baseline model is a model that predicts the prior probability of the majority or minority class depending on which is better (not available for savings score).If array-like, target probabilities of the baseline model.
Feature Add parameter validation for all models and samplers
API Change Make all arguments of dataset loaders keyword-only
Fix Update the descriptions attached to each dataset to match information found in the user guide
Fix Improve type hints for functions and classes
0.5.2 (12-01-2025)#
Feature Allow
savings_scoreandexpected_savings_scoreto calculate the savings score over the baseline model instead of a naive model, by setting they_pred_baselineandy_proba_baselineparameters, respectively.Enhancement Reworked the user guide documentation to better explain the usage of value-driven and cost-sensitive models, samplers and metrics
API Change
CSLogitClassifierandProfLogitClassifierby default do not perform soft-thresholding on the regression coefficients. This can be enabled by setting thesoft_thresholdparameter to True.Fix Prevent division by zero errors in
expected_cost_loss
0.5.1 (05-01-2025)#
Fix Fixed documentation build issue
0.5.0 (05-01-2025)#
Major Feature Added supported for python 3.13
- Major Feature Added cost-sensitive models
- Major Feature Added cost-sensitive metrics
Major Feature Added
empulse.datasetsmoduleFeature Added
CostSensitiveSamplerEnhancement Allow all cost-sensitive models and samplers to accept cost parameters during initialization
API Change Renamed metric arguments which expect target score from y_pred to y_score and target probabilities from y_pred to y_proba