flennerhag / mlens

ML-Ensemble – high performance ensemble learning
http://ml-ensemble.com
MIT License
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Questions on the meta-learner in Superlearner #131

Closed Skonar90 closed 4 years ago

Skonar90 commented 4 years ago

I recently started to use your Superlearner with some classifiers in the first layer and then the meta-learner. When I just do the first layer without the meta-learner there are some classifiers which perform way better in comparison to the case of the inclusion of the meta-learner?

How does the Meta-Learner Layer determine the weights of the previous layer?

Further, when i call the results you report "score-m ....", but which score is meant by this? When I calculate the score for the actual scorer i used i get something different? Thanks

flennerhag commented 4 years ago

The meta-learner is fitted using cross-validation, so the performance of the meta-learner depends on what class you are using and how much data you have. The original SuperLearner using a linear regression as the meta-learner. An even simpler method is to use majority voting (linear regression with weights fixed to 1).

when you create the ensemble, you pass in a score function. score-m is the mean value of score over cv-folds.