Soften Classification Targets with Label Smoothing
A classifier trained with one-hot targets receives a strong signal to push the target class probability toward one and every other class probability toward zero. Cross-entropy supports that behavior even after the predicted class is already correct: making the target probability more extreme can still reduce the loss. Label smoothing changes the target distribution before cross-entropy is computed. Instead of assigning all target mass to one class, it reserves a small amount for the remaining classes. This alters the gradient applied to the logits and reduces pressure toward extreme output distributions.