AI seminar: Extending Knowledge Base Update into First-Order Knowledge Bases

Date: May 27, 2008 (Tuesday) at 14:15

Prof. Witold Lukaszewicz, University of Warmia and Mazury and College of Informatics and Economics, Olsztyn, Poland, will hold the presentation "Extending Knowledge Base Update into First-Order Knowledge Bases"


Belief update is the task of modifying a knowledge base when an action is performed. More specifically, given a knowledge base KB, representing the world under consideration, and a formula alpha, representing an effect of an action, the task is to specify a new knowledge base, KB*alpha, representing the world after performing the action.

A number of different knowledge base update operators have been proposed in the literature. Ten of them are examined in a paper of Herzig and Rifi (Propositional Belief Base Update and Minimal Change. Artificial Intelligence Journal, 115(1):107-138, 1999). The conclusion they come to is that only two of the considered operators are satisfactory. One of them is MPMA, introduced by P. Doherty, W. Lukaszewicz and E. Madalinska-Bugaj in (The PMA and Relativizing Minimal Change for Action Update. Proceedings of the 6th International Conference on Principles of Knowledge Representation and Reasoning, KR-98, 158-169, 1998.)

All approaches to belief update are based on propositional logic what significantly restricts the use of these formalisms in practical applications. In this talk I generalize the MPMA update operator by admitting first-order knowledge bases and restricted first-order update formulae. This allows me to consider scenarios which cannot be properly formalized in existing approaches to belief update.

Room: E:2405

URL: http://ai.cs.lth.se/seminars.shtml

Last modified Dec 9, 2011 12:59 pm by Jacek.Malec@cs.lth.se