We define counting classes #P-R and #P-C in the Blum-Shub-Smale setting Of Computations over the real or complex numbers, respectively. The problems of counting the number of solutions of systems of polynomial inequal...
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We define counting classes #P-R and #P-C in the Blum-Shub-Smale setting Of Computations over the real or complex numbers, respectively. The problems of counting the number of solutions of systems of polynomial inequalities over R, or of systems of polynomial equalities over C, respectively, turn out to be natural complete problems in these classes. We investigate to what extent the new counting classes capture the complexity of computing basic topological invariants of semialgebraic sets (over R) and algebraic sets (over C). We prove that the problem of computing the Euler-Yao characteristic of semialgebraic sets is FP#(PR)-complete, and that the problem of computing the geometric degree of complex algebraic sets is FP#(RPC)(C) -complete. We also define new counting complexity classes in the classical Turing model via taking FPC complete. We, Boolean parts of the classes above, and show that the problems to compute the Euler characteristic and the geometric degree of (semi)algebraic sets given by integer polynomials are complete in these classes. We complement the results in the Turing model by proving, for all k is an element of N, the FPSPAGE-hardness of the problem of computing the kth Betti number ofthe set of real zeros of a given integer polynomial. This holds with respect to the singular homology as well as for the Borel-Moore homology. (c) 2005 Elsevier Inc. All rights reserved.
Abduction is an important method of non-monotonic reasoning with many applications in artificial intelligence and related topics. In this paper, we concentrate on propositional abduction, where the background knowledg...
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Abduction is an important method of non-monotonic reasoning with many applications in artificial intelligence and related topics. In this paper, we concentrate on propositional abduction, where the background knowledge is given by a propositional formula. Decision problems of great interest are the existence and the relevance problems. The complexity of these decision problems has been systematically studied while the counting complexity of propositional abduction has remained obscure. The goal of this work is to provide a comprehensive analysis of the counting complexity of propositional abduction in various settings. (C) 2009 Elsevier Inc. All rights reserved.
In this paper,we investigate the counting complexity of reachability problem for Boolean control networks(BCNs) by Boolean counting constraint satisfaction problem(#CSP).We prove that the counting complexity of a clas...
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ISBN:
(数字)9789887581536
ISBN:
(纸本)9781665482561
In this paper,we investigate the counting complexity of reachability problem for Boolean control networks(BCNs) by Boolean counting constraint satisfaction problem(#CSP).We prove that the counting complexity of a class of Boolean#CSP by using Post's lattice in universal algebra is#P-complete,and further use it to classify the counting complexity of M-reachability problem(#M-RP) when M=***,we prove that #M-RP is #P-complete.
We devise a framework for proving tight lower bounds under the counting exponentialtime hypothesis # ETHintroduced by Delletal.(2014) [18]. Our framework allows us to convert classical # P-hardness results for countin...
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We devise a framework for proving tight lower bounds under the counting exponentialtime hypothesis # ETHintroduced by Delletal.(2014) [18]. Our framework allows us to convert classical # P-hardness results for counting problems into tight lower bounds under # ETH, thus ruling out algorithms with running time 2(o(n)) on graphs with nvertices and O(n) edges. As exemplary applications of this framework, we obtain tight lower bounds under # ETHfor the evaluation of the zero-one permanent, the matching polynomial, and the Tutte polynomial on all non-easy points except for one line. This remaining line was settled very recently by Brand etal.(2016) [24]. (C) 2018 Elsevier Inc. All rights reserved.
Propositional circumscription, asking for the minimal models of a Boolean formula, is an important problem in artificial intelligence, in data mining, in coding theory, and in the model checking based procedures in au...
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Propositional circumscription, asking for the minimal models of a Boolean formula, is an important problem in artificial intelligence, in data mining, in coding theory, and in the model checking based procedures in automated reasoning. We consider the counting problems of propositional circumscription for several subclasses with respect to the structure of the formula. We prove that the counting problem of propositional circumscription for dual Horn, bijunctive, and affine formulas is #P-complete for a particular case of Turing reduction, whereas for Horn and 2affine formulas it is in FP. As a corollary, we obtain also the #P-completeness result for the counting problem of hypergraph transversal. (c) 2007 Elsevier B.V. All rights reserved.
We introduce and investigate a new type of reductions between counting problems, which we call subtractive reductions. We show that the main counting complexity classes #P, #NP, as well as all higher counting complexi...
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We introduce and investigate a new type of reductions between counting problems, which we call subtractive reductions. We show that the main counting complexity classes #P, #NP, as well as all higher counting complexity classes # (.) Pi P-k, k >= 2, are closed under subtractive reductions. We then pursue problems that are complete for these classes via subtractive reductions. We focus on the class #NP (which is the same as the class # (.) coNP) and show that it contains natural complete problems via subtractive reductions, such as the problem of counting the minimal models of a Boolean formula in conjunctive normal form and the problem of counting the cardinality of the set of minimal solutions of a homogeneous system of linear Diophantine inequalities. (c) 2005 Elsevier B.V. All rights reserved.
We de. ne a counting class #P-add in the Blum-Shub-Smale setting of additive computations over the reals. Structural properties of this class are studied, including a characterization in terms of the classical countin...
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We de. ne a counting class #P-add in the Blum-Shub-Smale setting of additive computations over the reals. Structural properties of this class are studied, including a characterization in terms of the classical counting class #P introduced by Valiant. We also establish transfer theorems for both directions between the real additive and the discrete setting. Then we characterize in terms of completeness results the complexity of computing basic topological invariants of semilinear sets given by additive circuits. It turns out that the computation of the Euler characteristic is FPadd#Padd-complete, while for fixed k the computation of the kth Betti number is FPAR(add)-complete. Thus the latter is more difficult under standard complexity theoretic assumptions. We use all of the above to prove some analogous completeness results in the classical setting.
We introduce and investigate a new type of reductions between counting problems, which we call subtractive reductions. We show that the main counting complexity classes #P, #NP, as well as all higher counting complexi...
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ISBN:
(纸本)3540679014
We introduce and investigate a new type of reductions between counting problems, which we call subtractive reductions. We show that the main counting complexity classes #P, #NP, as well as all higher counting complexity classes # (.) Pi P-k, k >= 2, are closed under subtractive reductions. We then pursue problems that are complete for these classes via subtractive reductions. We focus on the class #NP (which is the same as the class # (.) coNP) and show that it contains natural complete problems via subtractive reductions, such as the problem of counting the minimal models of a Boolean formula in conjunctive normal form and the problem of counting the cardinality of the set of minimal solutions of a homogeneous system of linear Diophantine inequalities. (c) 2005 Elsevier B.V. All rights reserved.
Following the approach of Hemaspaandra and Vollmer, we can define counting complexity classes #.C for any complexity class C of decision problems. In particular, the classes#. Pi(k)P with k >= 1 corresponding to al...
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Following the approach of Hemaspaandra and Vollmer, we can define counting complexity classes #.C for any complexity class C of decision problems. In particular, the classes#. Pi(k)P with k >= 1 corresponding to all levels of the polynomial hierarchy, have thus been studied. However, for a large variety of counting problems arising from optimization problems, a precise complexity classification turns out to be impossible with these classes. In order to remedy this unsatisfactory situation, we introduce a hierarchy of new counting complexity classes # . Opt(k)P and # . Opt(k)P[log n] with k >= 1. We prove several important properties of these new classes, like closure properties and the relationship with the # . Pi(k)P-classes. Moreover, we establish the completeness of several natural counting complexity problems for these new classes. (C) 2009 Elsevier B.V. All rights reserved.
We introduce a family of parameterised counting problems on graphs, p-#INDUCED SUBGRAPH WITH PROPERTY(Phi), which generalises a number of problems which have previously been studied. This paper focuses on the case in ...
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We introduce a family of parameterised counting problems on graphs, p-#INDUCED SUBGRAPH WITH PROPERTY(Phi), which generalises a number of problems which have previously been studied. This paper focuses on the case in which Phi defines a family of graphs whose edge-minimal elements all have bounded treewidth;this includes the special case in which Phi describes the property of being connected. We show that exactly counting the number of connected induced k-vertex subgraphs in an n-vertex graph is #W[1]-hard, but on the other hand there exists an FPTRAS for the problem;more generally, we show that there exists an FPTRAS for p-#INDUCED SUBGRAPH WITH PROPERTY(Phi) whenever Phi is monotone and all the minimal graphs satisfying Phi have bounded treewidth. We then apply these results to a counting version of the GRAPH MOTIF problem. (C) 2014 Elsevier Inc. All rights reserved.
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