@article{JarvisaloO:TPLP08,
author = {Matti J\"arvisalo and Emilia Oikarinen},
journal = {Theory and Practice of Logic Programming},
number = {5--6},
pages = {691--716},
title = {Extended {ASP} Tableaux and
Rule Redundancy in Normal Logic Programs},
volume = {8},
year = {2008},
}
Abstract:
We introduce an extended tableau calculus for answer set programming
(ASP). The proof system is based on the ASP tableaux defined in
[Gebser&Schaub, ICLP 2006], with an added extension rule. We investigate
the power of Extended ASP Tableaux both theoretically and empirically.
We study the relationship of Extended ASP Tableaux with the Extended
Resolution proof system defined by Tseitin for sets of clauses, and
separate Extended ASP Tableaux from ASP Tableaux by giving a
polynomial-length proof for a family of normal logic programs {P_n} for
which ASP Tableaux has exponential-length minimal proofs with respect to n.
Additionally, Extended ASP Tableaux imply interesting insight into the
effect of program simplification on the lengths of proofs in ASP.
Closely related to Extended ASP Tableaux, we empirically investigate the
effect of redundant rules on the efficiency of ASP solving.