Showing papers in "Journal of Computer and System Sciences in 2001"

TL;DR: A generalized reduction that is based on an algorithm that represents an arbitrary k-CNF formula as a disjunction of 2?nk-C NF formulas that are sparse, that is, each disjunct has O(n) clauses, and shows that Circuit-SAT is SERF-complete for all NP-search problems.

TL;DR: It is proved that marginal cost and Shapley value have a natural algorithm that uses only two messages per link of the multicast tree, while it is shown that the welfare value achieved by an optimal multicasts tree is NP-hard to approximate within any constant factor, even for bounded-degree networks.

TL;DR: This work considers the problem of selecting paths for routing in order to provide a bandwidth allocation that is as fair as possible (in the max?min sense), and gets the first approximation algorithms for this basic optimization problem, for single-source unsplittable routings in an arbitrary directed graph.

TL;DR: It is shown that when p<(1??)lnn /?n, an independent set of size |S| cannot be recovered, unless NP?BPP, and a heuristic is given that recovers this bisection with high probability when p?q?cplogn/n, for c a sufficiently large constant.

TL;DR: In this paper, a new general upper bound on the number of examples required to estimate all of the expectations of a set of random variables uniformly well is presented, and the quality of the estimates is measured using a variant of the relative error proposed by Haussler and Pollard.

TL;DR: In this paper, a new mathematical model of computation called Quantum Neural Networks (QNNs) is defined, building on Deutsch's model of quantum computational network, which introduces a nonlinear and irreversible gate, similar to the speculative operator defined by Abrams and Lloyd.

TL;DR: It is proved that if BPP?EXP, then every problem in BPP can be solved deterministically in subexponential time on almost every input (on every sampleable ensemble for infinitely many input sizes).

TL;DR: It is proved that the Minimum Equivalent DNF problem is ?

TL;DR: It is proved that every regular expression of size n can be converted into an equivalent nondeterministic ?

TL;DR: It is shown that by allowing O(logn) reroutes per call, the routing algorithm can achieve O( logn) competitive ratio with respect to the maximum load for the unknown duration case, where n is the number of nodes in the network.

TL;DR: A simple analytical framework for recommendation systems is introduced, including a basis for defining the utility of such a system, and probabilistic analyses of algorithms within this framework yield insights into how much utility can be derived from knowledge of past user actions.

TL;DR: The rigidity of a matrix measures the number of entries that must be changed in order to reduce its rank below a certain value and it is shown that the lower bound on a variant of rigidity implies lower bounds on size?depth trade-offs for arithmetic circuits with bounded coefficients computing linear transformations.

TL;DR: The definition of the quantum Kolmogorov complexity of a qubit string is defined as the length of the shortest quantum input to a universal quantum Turing machine that produces the initial qu bit string with high fidelity.

TL;DR: It is proved that every RP algorithm can be simulated by a zero-error probabilistic algorithm, running in expected subexponential time, that appears correct infinitely often (i.o. to every efficient adversary or EXP=ZPP) and that if ZPP is somewhat easy, then RP is subexponentially easy in the uniform setting described above.

TL;DR: A simple, constructive leader election protocol is given that is resilient against coalitions of size sn, for any s 0, and the perfect information model is adopted.

TL;DR: It is shown that metric MAX-CUT is NP-complete but has a polynomial time randomized approximation scheme.

TL;DR: It is proved that several global properties (global convergence, global asymptotic stability, mortality, and nilpotence) of particular classes of discrete time dynamical systems are undecidable.

TL;DR: This paper studies a class of problems, called distance realization problems, which arise in the study of Internet data traffic models, and shows that this weak realization problem is NP-complete and that its optimum solutions can be approximated to within a factor of 2.

TL;DR: New estimation results on the domain of attraction of memory patterns and exponential convergence rate of the network trajectories to memory patterns for Hopfield continuous associative memory are obtained and can be used for the evaluation of fault-tolerance capability and the synthesis procedures forHopfield continuous feedback Associative memory neural networks.

TL;DR: It is obtained that for any k, a function that requires exponential size to be computed by length knq-way branching programs, for some q=q(k) is given, which provides the first nontrivial time?space tradedoff for decision problems in this model.

TL;DR: An algorithm for the exact nearest neighbor in time bounded by O(dlogO(1)n) plus the number of (4?log1+?log4d?+1)-nearest neighbors of the query point is given and it is shown that for any c<3 the c-NNS problem in l∞ is provably as hard as the subset query problem

TL;DR: This paper presents online algorithms for routing and bandwidth allocation which simultaneously approximate fair and max-throughput solutions, and presents an O(log2nlog1+?U/?)-competitive algorithm, which is effective in attaining high throughput without significantly sacrificing fairness.

TL;DR: This paper presents several protocols in which the expected number of bits transmitted by the server and client are O(n) and O(H(D)+1), respectively, where H(D) is the binary entropy of D (and can range from 0 to n).

TL;DR: It is proven that FO with unary groupoidal quantifiers is strictly more expressive with predicates for plus and times than without, and it is proved that first-order logic with the “majority of pairs” quantifier is strictlyMore expressive than first- order with majority of individuals.

TL;DR: The paper develops a model-theoretic semantics, a fixpoint semantics, and an operational semantics for these constructs, and characterizes their power of expressing deterministic and nondeterministic queries.

TL;DR: This paper presents an efficient online agnostic learning algorithm for learning the class of constant-dimensional geometric patterns, which are more complex than any class of geometric patterns previously studied.

TL;DR: This paper presents a general recipe for an fds abstraction, which is shown to be sound, where soundness means that infeasibility of the abstracted fds implies infeasible of the unabstracted one, implying in turn the validity of the property over the concrete (infinite-state) system.

TL;DR: This paper studies the computational complexity, in the propositional case, of one of the main reasoning problems of belief revision and update: deciding if an interpretation M is a model of the revised knowledge base.

TL;DR: It is shown that for each ACTL formula ?

TL;DR: In this article, it was shown that the number of errors in Solomonoff sequence prediction is finite for computable distributions, if finite in the informed case, and that the deterministic variant of Solomonoff prediction is optimal compared to any other probabilistic or deterministic prediction scheme apart from additive square root corrections only.