Contracting preference relations for database applications

TL;DR

This paper explores preference contraction in binary relation frameworks, proposing algorithms for minimal and preference-protecting contractions, and analyzing their properties and applications in database preference handling.

Contribution

It introduces algorithms for minimal and preference-protecting contractions in finite and finitely representable preferences, with experimental evaluation and theoretical analysis.

Findings

Algorithms effectively compute minimal contractions

Preference protection constraints are feasible and effective

Experimental results validate the algorithms' efficiency

Abstract

The binary relation framework has been shown to be applicable to many real-life preference handling scenarios. Here we study preference contraction: the problem of discarding selected preferences. We argue that the property of minimality and the preservation of strict partial orders are crucial for contractions. Contractions can be further constrained by specifying which preferences should be protected. We consider two classes of preference relations: finite and finitely representable. We present algorithms for computing minimal and preference-protecting minimal contractions for finite as well as finitely representable preference relations. We study relationships between preference change in the binary relation framework and belief change in the belief revision theory. We also introduce some preference query optimization techniques which can be used in the presence of contraction. We evaluate the proposed algorithms experimentally and present the results.