English

Lexicographic Logic: a Many-valued Logic for Preference Representation

Artificial Intelligence 2020-12-22 v1 Logic in Computer Science

Abstract

Logical formalisms provide a natural and concise means for specifying and reasoning about preferences. In this paper, we propose lexicographic logic, an extension of classical propositional logic that can express a variety of preferences, most notably lexicographic ones. The proposed logic supports a simple new connective whose semantics can be defined in terms of finite lists of truth values. We demonstrate that, despite the well-known theoretical limitations that pose barriers to the quantitative representation of lexicographic preferences, there exists a subset of the rational numbers over which the proposed new connective can be naturally defined. Lexicographic logic can be used to define in a simple way some well-known preferential operators, like "AA and if possible BB", and "AA or failing that BB". Moreover, many other hierarchical preferential operators can be defined using a systematic approach. We argue that the new logic is an effective formalism for ranking query results according to the satisfaction level of user preferences.

Keywords

Cite

@article{arxiv.2012.10940,
  title  = {Lexicographic Logic: a Many-valued Logic for Preference Representation},
  author = {Angelos Charalambidis and Giorgos Papadimitriou and Panos Rondogiannis and Antonis Troumpoukis},
  journal= {arXiv preprint arXiv:2012.10940},
  year   = {2020}
}
R2 v1 2026-06-23T21:06:32.985Z