AI engineering glossary · Deep learning core

What is validation loss?

Validation loss: The loss measured on held-out data that the network does not train on. Watching it alongside training loss reveals overfitting: training loss keeps falling while validation loss stops improving or rises.

Level: beginnerTopic: Deep learning core

Validation loss: an example

Training loss of 0.1 with validation loss climbing from 0.4 to 0.6 across epochs signals memorisation.

Related terms

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Where you learn it

Validation loss 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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