Use of LBPHFaceRecognizer (python)

I am testing the python version of LBPHFaceRecognizer and results seems not bad, but I noted something strange. Making the prediction, let's say: label= face_recognizer.predict(gray) print('prediction', label) I see that `label` is a tuple with 2 values, the first is the prediction, the second I guess is the probability. Now when probability is low the prediction is fine, while when it is high, I have false positive. Maybe this value is not the probability, so the question is, what is its real meaning ? Thanks