Loss function

During training or testing, a mathematical function that calculates the loss on a batch of examples. A loss function returns a lower loss for models that makes good predictions than for models that make bad predictions.¹

The goal of training is typically to minimize the loss that a loss function returns.¹

Many different kinds of loss functions exist. Pick the appropriate loss function for the kind of model you are building. For example:¹

• L2 loss (or MSE) is the loss function for linear regression.
• Log loss is the loss function for logistic regression.

Footnotes

1. developers.google.com/machine-learning/glossary#loss-function ↩ ↩² ↩³