Distributing Knowledge into Simple Bases

Understanding the behavior of belief change operators for fragments of classical logic has received increasing interest over the last years. Results in this direction are mainly concerned with adapting representation theorems. However, fragment-driven belief change also leads to novel research questions. In this paper we propose the concept of belief distribution, which can be understood as the reverse task of merging. More specifically, we are interested in the following question: given an arbitrary knowledge base $K$ and some merging operator $\Delta$, can we find a profile $E$ and a constraint $\mu$, both from a given fragment of classical logic, such that $\Delta_\mu(E)$ yields a result equivalent to $K$? In other words, we are interested in seeing if $K$ can be distributed into knowledge bases of simpler structure, such that the task of merging allows for a reconstruction of the original knowledge. Our initial results show that merging based on drastic distance allows for an easy distribution of knowledge, while the power of distribution for operators based on Hamming distance relies heavily on the fragment of choice.

[1]  Yan Zhang,et al.  Definability of Horn Revision from Horn Contraction , 2013, IJCAI.

[2]  Stefan Woltran,et al.  A Model-Theoretic Approach to Belief Change in Answer Set Programming , 2013, TOCL.

[3]  G. G. Stokes "J." , 1890, The New Yale Book of Quotations.

[4]  Paolo Liberatore,et al.  Belief Merging by Examples , 2014, ACM Trans. Comput. Log..

[5]  Adrian Haret,et al.  Merging in the Horn Fragment , 2017, TOCL.

[6]  Stefan Woltran,et al.  Do Hard SAT-Related Reasoning Tasks Become Easier in the Krom Fragment? , 2013, IJCAI.

[7]  Nils J. Nilsson,et al.  Artificial Intelligence , 1974, IFIP Congress.

[8]  Sébastien Konieczny,et al.  Distance Based Merging: A General Framework and some Complexity Results , 2002, KR.

[9]  Maurice Pagnucco,et al.  Model Based Horn Contraction , 2012, KR.

[10]  Paolo Liberatore,et al.  Revision History , 1995 .

[11]  Andrew Josey Updates , 2003, login Usenix Mag..

[12]  Georg Gottlob,et al.  On the complexity of propositional knowledge base revision, updates, and counterfactuals , 1992, Artif. Intell..

[13]  Pierre Marquis,et al.  A Knowledge Compilation Map , 2002, J. Artif. Intell. Res..

[14]  Stefan Woltran,et al.  Belief revision within fragments of propositional logic , 2012, J. Comput. Syst. Sci..

[15]  Marco Schaerf,et al.  Belief Revision and Update: Complexity of Model Checking , 2001, J. Comput. Syst. Sci..

[16]  Blai Bonet,et al.  Proceedings of the Twenty-Ninth AAAI Conference on Artificial Intelligence, January 25-30, 2015, Austin, Texas, USA , 2015, AAAI.

[17]  Sébastien Konieczny,et al.  DA2 merging operators , 2004, Artif. Intell..

[18]  Hirofumi Katsuno,et al.  Propositional Knowledge Base Revision and Minimal Change , 1991, Artif. Intell..

[19]  Maurice Pagnucco,et al.  Entrenchment-Based Horn Contraction , 2014, J. Artif. Intell. Res..

[20]  Pierre Marquis,et al.  Disjunctive closures for knowledge compilation , 2014, Artif. Intell..

[21]  James P. Delgrande,et al.  Belief revision in Horn theories , 2015, Artif. Intell..

[22]  M. Panella Associate Editor of the Journal of Computer and System Sciences , 2014 .

[23]  Peter Gärdenfors,et al.  On the logic of theory change: Partial meet contraction and revision functions , 1985, Journal of Symbolic Logic.

[24]  Stefan Rümmele,et al.  Belief Merging within Fragments of Propositional Logic , 2016, TOCL.

[25]  Sébastien Konieczny,et al.  Merging Information Under Constraints: A Logical Framework , 2002, J. Log. Comput..

[26]  Leonid Libkin Proceedings of the Twenty-Fourth International Joint Conference on Artificial Intelligence (IJCAI 2015) , 2015, AAAI 2015.