AI engineering glossary · ML fundamentals

What is underfitting?

Underfitting: When a model is too simple or too little trained to capture the real pattern in the data, so it performs poorly even on its own training set. Fixes include using a more flexible model, adding informative features or reducing regularisation.

Level: beginnerTopic: ML fundamentals

Underfitting: an example

Fitting a straight line to data that clearly follows a curve leaves large errors on both training and test data.

Related terms

More ML fundamentals terms

Where you learn it

Underfitting 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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