really measure how much we're overfitting because you wouldn't really expect the model to perfectly copy a training example it's more likely that it would mostly copy the training example and then kind of change a few small things about it and we do things like look for nearest neighbors we generate samples and then see the most similar training example in terms of Euclidean distances but it's really easy to make a small change that causes a gigantic difference in Euclidean distance so that can be kind of hard to tell if it's actually