there's a car in a photo or not then the answer is pretty unambiguous either there is a car or there isn't in in medical imaging our training data is often imperfect ie if you ask three different radiologists that will give you hopefully not three different answers but they might give you more than one answer so you really need to train in a scenario where your data might not be perfectly labeled and of course if that's then not perfectly labeled how do you actually validate your algorithm against something where