DEALING WITH LINGUISTIC NEGATION: A MATTER OF STANDARD FORMS AND APPROXIMATION SETS

摘要

The main object of this paper is to give an affirmative translation, when it exists, to a negative expression. The study more especially insists on vague information referring to linguistic negation, rather than to logical one. Our work is based on the standard forms of linguistic negation interpretations represented as "x is not A". The reference frame associated with a standard form contains all its positive interpretations. The main goal of dealing with negation is the selection of one (or several) positive interpretation(s) associated with a negative sentence from its reference frame. The originality of our approach results from the fact that we do not search directly all affirmative interpretations of a negative sentence, but we approximate its significance. Our approach is based on a neighborhood relation defined on the space of properties. This relation allows us to introduce two operators according to rough set theory, one being optimistic and the other pessimistic. Finally, we propose a choice strategy of the intended meaning of a linguistic negation.