Complexity of finding embeddings in a k-tree
SIAM Journal on Algebraic and Discrete Methods
Tree clustering for constraint networks (research note)
Artificial Intelligence
A Computing Procedure for Quantification Theory
Journal of the ACM (JACM)
A comparison of structural CSP decomposition methods
Artificial Intelligence
A Benchmark Method for the Propositional Modal Logics K, KT, S4
Journal of Automated Reasoning
Resolution versus Search: Two Strategies for SAT
Journal of Automated Reasoning
Bounded Model Construction for Monadic Second-Order Logics
CAV '00 Proceedings of the 12th International Conference on Computer Aided Verification
Conflict driven learning in a quantified Boolean Satisfiability solver
Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design
Word problems requiring exponential time(Preliminary Report)
STOC '73 Proceedings of the fifth annual ACM symposium on Theory of computing
A complete anytime algorithm for treewidth
UAI '04 Proceedings of the 20th conference on Uncertainty in artificial intelligence
Fixed-Parameter Hierarchies inside PSPACE
LICS '06 Proceedings of the 21st Annual IEEE Symposium on Logic in Computer Science
Data Mining
Treewidth: A Useful Marker of Empirical Hardness in Quantified Boolean Logic Encodings
LPAR '08 Proceedings of the 15th International Conference on Logic for Programming, Artificial Intelligence, and Reasoning
AAAI'07 Proceedings of the 22nd national conference on Artificial intelligence - Volume 1
Clause/term resolution and learning in the evaluation of quantified Boolean formulas
Journal of Artificial Intelligence Research
Backtracking procedures for hypertree, hyperspread and connected hypertree decomposition of CSPs
IJCAI'07 Proceedings of the 20th international joint conference on Artifical intelligence
The complexity of quantified constraint satisfaction problems under structural restrictions
IJCAI'05 Proceedings of the 19th international joint conference on Artificial intelligence
Bounded universal expansion for preprocessing QBF
SAT'07 Proceedings of the 10th international conference on Theory and applications of satisfiability testing
Complexity of K-tree structured constraint satisfaction problems
AAAI'90 Proceedings of the eighth National conference on Artificial intelligence - Volume 1
Mapping conformant planning into SAT through compilation and projection
CAEPIA'05 Proceedings of the 11th Spanish association conference on Current Topics in Artificial Intelligence
CP'06 Proceedings of the 12th international conference on Principles and Practice of Constraint Programming
SAT'04 Proceedings of the 7th international conference on Theory and Applications of Satisfiability Testing
SAT'04 Proceedings of the 7th international conference on Theory and Applications of Satisfiability Testing
SAT'05 Proceedings of the 8th international conference on Theory and Applications of Satisfiability Testing
Bounded model checking with QBF
SAT'05 Proceedings of the 8th international conference on Theory and Applications of Satisfiability Testing
sKizzo: a suite to evaluate and certify QBFs
CADE' 20 Proceedings of the 20th international conference on Automated Deduction
CSL'05 Proceedings of the 19th international conference on Computer Science Logic
Quantifier Structure in Search-Based Procedures for QBFs
IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Fundamenta Informaticae - RCRA 2008 Experimental Evaluation of Algorithms for Solving Problems with Combinatorial Explosion
Hi-index | 0.00 |
From an empirical point of view, the hardness of quantified Boolean formulas (QBFs), can be characterized by the (in)ability of current state-of-the-art QBF solvers to decide about the truth of formulas given limited computational resources. In this paper, we start from the problem of computing empirical hardness markers, i.e., features that can discriminate between hard and easy QBFs, and we end up showing that such markers can be useful to improve our understanding of QBF preprocessors. In particular, considering the connection between classes of tractable QBFs and the treewidth of associated graphs, we show that (an approximation of) treewidth is indeed a marker of empirical hardness and it is the only parameter which succeeds consistently in being so, even considering several other purely syntactic candidates which have been successfully employed to characterize QBFs in other contexts. We also show that treewidth approximations can be useful to describe the effect of QBF preprocessors, in that some QBF solvers benefit from a preprocessing phase when it reduces the treewidth of their input. Our experiments suggest that structural simplifications reducing treewidth are a potential enabler for the solution of hard QBF encodings.