[scikit-learn] Opinion on reference mentioning that RF uses weak learners

2020-08-16 Thread Fernando Marcos Wittmann
Hello guys, The the following reference states that Random Forests uses weak learners: - https://blog.citizennet.com/blog/2012/11/10/random-forests-ensembles-and-performance-metrics#:~:text=The%20random%20forest%20starts%20with,corresponds%20to%20our%20weak%20learner.&text=Thus%2C%20in%20ensemble%

Re: [scikit-learn] Opinion on reference mentioning that RF uses weak learners

2020-08-16 Thread Matthieu Brucher
Hi, What are you wondering? The individual tree is weakened by design (accepts more errors), so indeed, the individual trees are weak learners and the combination of them (the forest) becomes the strong learner. You can have a strong tree as well (deeper, more parameters), but that's not what is s

Re: [scikit-learn] Opinion on reference mentioning that RF uses weak learners

2020-08-16 Thread Guillaume LemaƮtre
One needs to define what is the definition of weak learner.In boosting, if I recall well the literature, weak learner refers to learner which unfit performing slightly better than a random learner. In this regard, a tree with shallow depth will be a weak learner and is used in adaboost or gradien

Re: [scikit-learn] Opinion on reference mentioning that RF uses weak learners

2020-08-16 Thread Nicolas Hug
As previously mentioned, a "weak learner" is just a learner that barely performs better than random. It's more common in the context of boosting, but I think weak learning predates boosting, and the original RF paper by Breiman does make reference to "weak learners": It's interesting that Fore

Re: [scikit-learn] Opinion on reference mentioning that RF uses weak learners

2020-08-16 Thread Fernando Marcos Wittmann
In my opinion the reference is distorting a concept that has a consolidated definition in the community. I am also familiar with the definition of WL as "an estimator slightly better than guessing", mostly decision stumps ( https://en.m.wikipedia.org/wiki/Decision_stump), which is not an component

Re: [scikit-learn] Opinion on reference mentioning that RF uses weak learners

2020-08-16 Thread Brown J.B. via scikit-learn
> As previously mentioned, a "weak learner" is just a learner that barely performs better than random. To continue with what the definition of a random learner refers to, does it mean the following contexts? (1) Classification: a learner which uniformly samples from one of the N endpoints in the t