What is a learning cycle mentioned in the 'fitcensemble' documentation

What does the term 'learning cycle' refer to. It is mentioned in the 'fitcensemble' documentation.

Answer 1

[Drew]

See the "NumLearningCycles" section on the page https://www.mathworks.com/help/stats/fitcensemble.html.

The info from there:

NumLearningCycles — Number of ensemble learning cycles

100 (default) | positive integer | 'AllPredictorCombinations'

Number of ensemble learning cycles, specified as the comma-separated pair consisting of 'NumLearningCycles' and a positive integer or 'AllPredictorCombinations'.

• If you specify a positive integer, then, at every learning cycle, the software trains one weak learner for every template object in Learners. Consequently, the software trains NumLearningCycles*numel(Learners) learners.
• If you specify 'AllPredictorCombinations', then set Method to 'Subspace' and specify one learner only for Learners. With these settings, the software trains learners for all possible combinations of predictors taken NPredToSample at a time. Consequently, the software trains nchoosek(size(X,2),NPredToSample) learners.

The software composes the ensemble using all trained learners and stores them in Mdl.Trained.

For more details, see Tips.

Example: 'NumLearningCycles',500

Data Types: single | double | char | string