Mean absolute error (MAE) Group of answer choices The average of the difference between the ground truth and the predicted values The average of the squared difference between the target value and the value predicted by the regression model An indicator of the model's performance when all classes are equally important, measured as the proportion of correctly predicted events to all predicted events The ratio of positive samples that were correctly classified to all samples that were classified as positive (either correctly or incorrectly); measures how well the model classifies a sample as positive