Отрицательный класс — class label, представляющая отсутствие condition или outcome of interest в binary classification task. Например, в spam detection «not spam» часто рассматривается как negative class.
In binary classification, one class is termed positive and the other is termed negative. The positive class is the thing or event that the model is testing for and the negative class is the other possibility. For example: - The negative class in a medical test might be "not tumor." - The negative class in an email classification model might be "not spam." Contrast with positive class.