AI engineering glossary · Classical ML algorithms

What is out-of-bag error?

Out-of-bag error (also called OOB error): An error estimate for bagged models that uses the rows each tree did not see in its bootstrap sample. Every row is predicted only by trees that left it out, so the score behaves like validation data without setting any data aside.

Level: intermediateTopic: Classical ML algorithms

Out-of-bag error: an example

Setting oob_score=True in RandomForestClassifier reports 0.86 accuracy measured on the left-out rows of each tree.

Related terms

More Classical ML algorithms terms

Where you learn it

Out-of-bag error is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.

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