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Found 16 papers, 3 papers with code
Counting Solutions to Conjunctive Queries: Structural and Hybrid Tractability
Counting the number of answers to conjunctive queries is a fundamental problem in databases that, under standard assumptions, does not have an efficient solution.
Subtractive Mixture Models via Squaring: Representation and Learning
Mixture models are traditionally represented and learned by adding several distributions as components.
Bounds on BDD-Based Bucket Elimination
We also show that the more common implementation of bucket elimination using the same order for variable elimination and the BDDs has exponential runtime for the pigeonhole principle when using either of the two orders from our upper bound, which suggests that the combination of both is the key to efficiency in the setting.
No Efficient Disjunction or Conjunction of Switch-Lists
It is shown that disjunction of two switch-lists can blow up the representation size exponentially.
Proof Complexity of Symbolic QBF Reasoning
We introduce and investigate symbolic proof systems for Quantified Boolean Formulas (QBF) operating on Ordered Binary Decision Diagrams (OBDDs).
An extended Knowledge Compilation Map for Conditional Preference Statements-based and Generalized Additive Utilities-based Languages
Conditional preference statements have been used to compactly represent preferences over combinatorial domains.
On Irrelevant Literals in Pseudo-Boolean Constraint Learning
Learning pseudo-Boolean (PB) constraints in PB solvers exploiting cutting planes based inference is not as well understood as clause learning in conflict-driven clause learning solvers.
Lower Bounds for Approximate Knowledge Compilation
Moreover, there are known size lower bounds for d-DNNF which by relaxing to approximation one might be able to avoid.
Constant-Delay Enumeration for Nondeterministic Document Spanners
We refute this and show that, given a nondeterministic sequential VA and an input document, we can enumerate the mappings of the VA on the document with the following bounds: the preprocessing is linear in the document size and polynomial in the size of the VA, and the delay is independent of the document and polynomial in the size of the VA.
Graph Width Measures for CNF-Encodings with Auxiliary Variables
Here we consider the expressivity of these formulas in the model of clausal encodings with auxiliary variables.
Constant-Delay Enumeration for Nondeterministic Document Spanners
We refute this and show that, given a nondeterministic sequential VA and an input document, we can enumerate the mappings of the VA on the document with the following bounds: the preprocessing is linear in the document size and polynomial in the size of the VA, and the delay is independent of the document and polynomial in the size of the VA.
QBF as an Alternative to Courcelle's Theorem
We propose reductions to quantified Boolean formulas (QBF) as a new approach to showing fixed-parameter linear algorithms for problems parameterized by treewidth.
Parameterized Compilation Lower Bounds for Restricted CNF-formulas
We show unconditional parameterized lower bounds in the area of knowledge compilation, more specifically on the size of circuits in decomposable negation normal form (DNNF) that encode CNF-formulas restricted by several graph width measures.
Minimal Distance of Propositional Models
We investigate the complexity of three optimization problems in Boolean propositional logic related to information theory: Given a conjunctive formula over a set of relations, find a satisfying assignment with minimal Hamming distance to a given assignment that satisfies the formula ($\mathsf{NeareastOtherSolution}$, $\mathsf{NOSol}$) or that does not need to satisfy it ($\mathsf{NearestSolution}$, $\mathsf{NSol}$).
Computational Complexity
Understanding model counting for $β$-acyclic CNF-formulas
We extend the knowledge about so-called structural restrictions of $\mathrm{\#SAT}$ by giving a polynomial time algorithm for $\beta$-acyclic $\mathrm{\#SAT}$.
Hypergraph Acyclicity and Propositional Model Counting
We show that the propositional model counting problem #SAT for CNF- formulas with hypergraphs that allow a disjoint branches decomposition can be solved in polynomial time.
