AIExplainer

What is a training loss?

A metric representing a model's loss during a particular training iteration.

A metric representing a model's loss during a particular training iteration. For example, suppose the loss function is Mean Squared Error. Perhaps the training loss (the Mean Squared Error) for the 10th iteration is 2.2, and the training loss for the 100th iteration is 1.9. A loss curve plots training loss versus the number of iterations. A loss curve provides the following hints about training: - A downward slope implies that the model is improving. - An upward slope implies that the model is getting worse. - A flat slope implies that the model has reached convergence. For example, the following somewhat idealized loss curve shows: - A steep downward slope during the initial iterations, which implies rapid model improvement. - A gradually flattening (but still downward) slope until close to the end of training, which implies continued model improvement at a somewhat slower pace then during the initial iterations. - A flat slope towards the end of training, which suggests convergence. Although training loss is important, see also generalization.

Practitioners refer to training loss when building, training, or evaluating machine learning systems. It appears in research papers, product documentation, and technical discussions about AI capabilities and limitations.