AI engineering glossary · ML fundamentals

What is generalisation error?

Generalisation error (also called Test error): The expected error of a model on new data drawn from the same source as its training data. It is approximated by error on a held-out test set, and it is what training is really trying to make small.

Level: intermediateTopic: ML fundamentals

Generalisation error: an example

A model with 4% training error and 11% error on a fresh test set has an estimated value of about 11%.

Related terms

More ML fundamentals terms

Where you learn it

Generalisation 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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