We have a text classifcation setup where users can select multiple non-mutually-exclusive categories for a given text. Now I'm wondering about the purpose of the reject button in such a case. Is it designed to classify True Negatives? Because if so, isn't it the case that not choosing any category should fulfill the same purpose? I.e. if not a single one of the categories is assigned and the user clicks on accept, isn't then the absence of assigned categories a defining marker of a true negative?
If so, what's the purpose of the reject button?
If the setup were a binary classification as shown in your textcat.teach examples it would make sense as there the button boils down to the only question of 'binary category yes / binary category no'. But with multiple categories I don't see the purpose.
And if it is not needed indeed, can I disable it? From other posts it seems as hiding it via css seems the way to go, is that right?