Variant of the squared loss that is robust to outliers.
Returns the loss.
Return the gradient with respect to y_pred.
This is the inverse of the link function. Typically, a loss function takes as input the raw output of a model. In the case of classification, the raw output would be logits. The mean function can be used to convert the raw output into a value that makes sense to the user, such as a probability.
The adjusted prediction(s).