Proceedings 39th Annual Symposium on Foundations of Computer Science (Cat. No.98CB36280)

8-11 Nov. 1998

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  • Proceedings 39th Annual Symposium on Foundations of Computer Science (Cat. No.98CB36280)

    Publication Year: 1998
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    Freely Available from IEEE
  • Geometric computation and the art of sampling (tutorial)

    Publication Year: 1998, Page(s): 2
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (7 KB)

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  • A tutorial on theoretical issues in probabilistic artificial intelligence

    Publication Year: 1998, Page(s): 4
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  • Author index

    Publication Year: 1998, Page(s):744 - 745
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    Freely Available from IEEE
  • Quantum lower bounds by polynomials

    Publication Year: 1998, Page(s):352 - 361
    Cited by:  Papers (28)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (180 KB)

    We examine the number T of queries that a quantum network requires to compute several Boolean functions on {0,1}N in the black-box model. We show that, in the black-box model, the exponential quantum speed-up obtained for partial functions (i.e. problems involving a promise on the input) by Deutsch and Jozsa and by Simon cannot be obtained for any total function: if a quantum algorithm ... View full abstract»

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  • All pairs shortest paths in weighted directed graphs-exact and almost exact algorithms

    Publication Year: 1998, Page(s):310 - 319
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (172 KB)

    We present two new algorithms for solving the All Pairs Shortest Paths (APSP) problem for weighted directed graphs. Both algorithms use fast matrix multiplication algorithms. The first algorithm solves the APSP problem for weighted directed graphs in which the edge weights are integers of small absolute value in O˜(n2+μ) time, where μ satisfies the equation ω(1,μ,1)... View full abstract»

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  • Decidability of bisimulation equivalence for equational graphs of finite out-degree

    Publication Year: 1998, Page(s):120 - 129
    Cited by:  Papers (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (248 KB)

    The bisimulation problem for equational graphs of finite out-degree is shown to be decidable. We reduce this problem to the η-bisimulation problem for deterministic rational (vectors of) Boolean series on the alphabet of a dpda M. We then exhibit a complete formal system for deducing equivalent pairs of such vectors View full abstract»

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  • Faster and simpler algorithms for multicommodity flow and other fractional packing problems

    Publication Year: 1998, Page(s):300 - 309
    Cited by:  Papers (145)  |  Patents (13)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (176 KB)

    This paper considers the problem of designing fast, approximate, combinatorial algorithms for multicommodity flows and other fractional packing problems. We provide a different approach to these problems which yields faster and much simpler algorithms. Our approach also allows us to substitute shortest path computations for min-cost flow computations in computing maximum concurrent flow and min-co... View full abstract»

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  • The quantum communication complexity of sampling

    Publication Year: 1998, Page(s):342 - 351
    Cited by:  Papers (10)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (268 KB)

    Sampling is an important primitive in probabilistic and quantum algorithms. In the spirit of communication complexity, given a function f: X×Y→{0,1} and a probability distribution D over X×Y, we define the sampling complexity of (f,D) as the minimum number of bits Alice and Bob must communicate for Alice to pick x∈X and Bob to pick y∈Y as well as a valve z s.t. the resul... View full abstract»

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  • Satisfiability of word equations with constants is in exponential space

    Publication Year: 1998, Page(s):112 - 119
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (124 KB)

    In this paper we study solvability of equations over free semigroups, known as word equations, particularly G.S. Makanin's algorithm (1977), a general procedure to decide if a word equation has a solution. The upper bound time-complexity of Makanin's original decision procedure was quadruple exponential in the length of the equation, as shown by Jaffar. A. Koscielski and L. Pacholski (1996) reduce... View full abstract»

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  • Multiplicative complexity of Taylor shifts and a new twist of the substitution method

    Publication Year: 1998, Page(s):212 - 215
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (100 KB)

    Let Cn=Cn(K) denote the minimum number of essential multiplications/divisions required for shifting a general n-th degree polynomial A(t)=Σaiti to some new origin x, which means to compute the coefficients bk of the Taylor expansion A(x+t)=B(t)=Σbktk as elements of K(x,a0,...,an) with ind... View full abstract»

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  • Testing monotonicity

    Publication Year: 1998, Page(s):426 - 435
    Cited by:  Papers (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (180 KB)

    We present a (randomized) test for monotonicity of Boolean functions. Namely, given the ability to query an unknown function f: {0, 1}n-{0, 1} at arguments of its choice, the test always accepts a monotone f, and rejects f with high probability if it is ε-far from being monotone (i.e., every monotone function differs from f on more than an ε fraction of the domain). The comple... View full abstract»

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  • Approximating-CVP to within almost-polynomial factors is NP-hard

    Publication Year: 1998, Page(s):99 - 109
    Cited by:  Papers (22)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (184 KB)

    This paper shows the closest vector in a lattice to be NP-hard to approximate to within any factor up to 2(logn)1-4 where ε=(loglogn)-c for any constant c<½ View full abstract»

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  • On the combinatorial and topological complexity of a single cell

    Publication Year: 1998, Page(s):606 - 616
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (172 KB)

    The problem of bounding the combinatorial complexity of a single connected component (a single cell) of the complement of a set of a geometric objects in Rk, each object of constant description complexity, is an important problem in computational geometry which has attracted much attention over the past decade. It has been conjectured that the combinatorial complexity of a single cell i... View full abstract»

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  • On the single-source unsplittable flow problem

    Publication Year: 1998, Page(s):290 - 299
    Cited by:  Papers (10)  |  Patents (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (172 KB)

    Let G=(V,E) be a capacitated directed graph with a source s and k terminals ti with demands di, 1⩽i⩽k. We would like to concurrently route every demand on a single path from s to the corresponding terminal without violating the capacities. There are several interesting and important variations of this unsplittable flow problem. If the necessary cut condition is satisf... View full abstract»

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  • Unsatisfiable systems of equations, over a finite field

    Publication Year: 1998, Page(s):202 - 211
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (156 KB)

    The properties of any system of k simultaneous equations in n variables over GF(q), are studied, with a particular emphasis on unsatisfiable systems. A general formula for the number of solutions is given, which can actually be useful for computing that number in the special case where all the equations are of degree 2. When such a quadratic system has no solution, there is always a proof of unsat... View full abstract»

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  • Delayed information and action in on-line algorithms

    Publication Year: 1998, Page(s):71 - 80
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (152 KB)

    Most on-line analysis assumes that, at each time-step, all relevant information up to that time step is available and a decision has an immediate effect. In many on-line problems, however, the time relevant information is available and the time a decision has an effect may be decoupled. For example, when making an investment, one might not have completely up-to-date information on market prices. S... View full abstract»

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  • Orchestrating quartets: approximation and data correction

    Publication Year: 1998, Page(s):416 - 425
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (152 KB)

    Inferring evolutionary trees has long been a challenging problem both for biologists and computer scientists. In recent years research has concentrated on the quartet method paradigm for inferring evolutionary trees. Quartet methods proceed by first inferring the evolutionary history for every set of four species (resulting in a set Q of inferred quarter topologies) and then recombining these infe... View full abstract»

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  • A factor 2 approximation algorithm for the generalized Steiner network problem

    Publication Year: 1998, Page(s):448 - 457
    Cited by:  Papers (10)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (132 KB)

    We present a factor 2 approximation algorithm for finding a minimum-cost subgraph having at least a specified number of edges in each cut. This class of problems includes, among others, the generalized Steiner network problem, which is also known as the survivable network design problem. Our algorithm first solves the linear relaxation of this problem, and then iteratively rounds off the solution.... View full abstract»

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  • An improved exponential-time algorithm for k-SAT

    Publication Year: 1998, Page(s):628 - 637
    Cited by:  Papers (18)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (184 KB)

    We propose and analyze a simple new algorithm for finding satisfying assignments of Boolean formulae in conjunctive normal form. The algorithm, ResolveSat, is a randomized variant of the DDL procedure by M. Davis et al. (1962) or Davis-Putnam procedure. Rather than applying the DLL procedure to the input formula F, however; ResolveSat enlarges F by adding additional clauses using limited resolutio... View full abstract»

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  • The shortest vector in a lattice is hard to approximate to within some constant

    Publication Year: 1998, Page(s):92 - 98
    Cited by:  Papers (18)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (140 KB)

    We show the shortest vector problem in the l2 norm is NP-hard (for randomized reductions) to approximate within any constant factor less than √2. We also give a deterministic reduction under a reasonable number theoretic conjecture. Analogous results hold in any lp norm (p⩾1). In proving our NP-hardness result, we give an alternative construction satisfying Ajtai's ... View full abstract»

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  • A tight characterization of NP with 3 query PCPs

    Publication Year: 1998, Page(s):8 - 17
    Cited by:  Papers (11)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (168 KB)

    It is known that there exists a PCP characterization of NP where the verifier makes 3 queries and has a one-sided error that is bounded away from 1; and also that 2 queries do not suffice for such a characterization. Thus PCPs with 3 queries possess non-trivial verification power and motivate the task of determining the lowest error that can be achieved with a 3-query PCP. Recently, Hastad (1997) ... View full abstract»

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  • Parametric and kinetic minimum spanning trees

    Publication Year: 1998, Page(s):596 - 605
    Cited by:  Papers (16)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (96 KB)

    We consider the parametric minimum spanning tree problem, in which we are given a graph with edge weights that are linear functions of a parameter λ and wish to compute the sequence of minimum spanning trees generated as λ varies. We also consider the kinetic minimum spanning tree problem, in which λ represents time and the graph is subject in addition to changes such as edge ... View full abstract»

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  • Perfect information leader election in log*n+O(1) rounds

    Publication Year: 1998, Page(s):576 - 583
    Cited by:  Papers (7)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (124 KB)

    In the leader election problem, n players wish to elect a random leader. The difficulty is that some coalition of players may conspire to elect one of its own members. We adopt the perfect information model: all communication is by broadcast, and the bad players have unlimited computational power. Within a round, they may also wait to see the inputs of the good players. A protocol is called resili... View full abstract»

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  • The minimum equivalent DNF problem and shortest implicants

    Publication Year: 1998, Page(s):556 - 563
    Cited by:  Papers (11)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (124 KB)

    We prove that the Minimum Equivalent DNF problem is Σ2 p-complete, resolving a conjecture due to L.J. Stockmeyer (1976). The proof involves as an intermediate step a variant of a related problem in logic minimization, namely, that of finding the shortest implicant of a Boolean function. We also obtain certain results concerning the complexity of the shortest implicant p... View full abstract»

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