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40th Annual Symposium on Foundations of Computer Science (Cat. No.99CB37039)

17-19 Oct. 1999

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  • 40th Annual Symposium on Foundations of Computer Science (Cat. No.99CB37039)

    Publication Year: 1999
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    Freely Available from IEEE
  • Near-optimal conversion of hardness into pseudo-randomness

    Publication Year: 1999, Page(s):181 - 190
    Cited by:  Papers (9)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (180 KB)

    Various efforts have been made to derandomize probabilistic algorithms using the assumption that there exists a problem in E=dtime(2/sup O(n)/) that requires circuits of size s(n) (for some function s). These results are based on the NW (Nisan & Wigderson, 1997) generator. For the strong lower bound s(n)=2/sup ϵn/, the optimal derandomization is P=BPP. However, for weaker lower bound funct... View full abstract»

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  • Author index

    Publication Year: 1999, Page(s):667 - 668
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    Freely Available from IEEE
  • Finely-competitive paging

    Publication Year: 1999, Page(s):450 - 457
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (120 KB)

    We construct an online algorithm for paging that achieves an O(r+log k) competitive ratio when compared to an offline strategy that is allowed the additional ability to “rent” pages at a cost of 1/r. In contrast, the competitive ratio of the Marking algorithm for this scenario is O(r log k). Our algorithm can be thought of in the standard setting as having a “fine-grained” ... View full abstract»

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  • Weak adversaries for the k-server problem

    Publication Year: 1999, Page(s):444 - 449
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (112 KB)

    We study the k-server problem when the offline algorithm has fewer than k servers. We give two upper bounds of the cost WFA(ρ) of the Work Function Algorithm. The first upper bound is kOPTh(ρ)+(h-1)OPTk(ρ), where OPTm (ρ) denotes the optimal cost to service ρ by m servers. The second upper bound is 2hOPTh(ρ)-OPTk(ρ) for h⩽... View full abstract»

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  • Online scheduling to minimize average stretch

    Publication Year: 1999, Page(s):433 - 443
    Cited by:  Papers (16)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (176 KB)

    We consider the classical problem of online job scheduling on uniprocessor and multiprocessor machines. For a given job, we measure the quality of service provided by an algorithm by the stretch of the job, which is defined as the ratio of the amount of time that the job spends in the system to the processing time of the job. For a given sequence of jobs, we measure the performance of an algorithm... View full abstract»

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  • A study of proof search algorithms for resolution and polynomial calculus

    Publication Year: 1999, Page(s):422 - 431
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (180 KB)

    The paper is concerned with the complexity of proofs and of searching for proofs in two propositional proof systems: Resolution and Polynomial Calculus (PC). For the former system we show that the recently proposed algorithm of E. Ben-Sasson and A. Wigderson (1999) for searching for proofs cannot give better than weakly exponential performance. This is a consequence of showing optimality of their ... View full abstract»

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  • A near-tight lower bound on the time complexity of distributed MST construction

    Publication Year: 1999, Page(s):253 - 261
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (312 KB)

    This paper presents a lower bound of Ω¯(D+√n) on the time required for the distributed construction of a minimum-weight spanning tree (MST) in n-vertex networks of diameter D=Ω(log n), in the bounded message model. This establishes the asymptotic near-optimality of existing time-efficient distributed algorithms for the problem, whose complexity is O(D+√nlog* n) View full abstract»

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  • Random CNFs are hard for the polynomial calculus

    Publication Year: 1999, Page(s):415 - 421
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (148 KB)

    We show a general reduction that derives lower bounds on degrees of polynomial calculus proofs of tautologies, over any field of characteristic (other than 2) from lower bounds for resolution proofs of a related set of linear equations module 2. We apply this to derive linear lower bounds on the degrees of PC proofs of randomly generated tautologies View full abstract»

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  • Markovian coupling vs. conductance for the Jerrum-Sinclair chain

    Publication Year: 1999, Page(s):241 - 251
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (188 KB)

    We show that no Markovian coupling argument can prove rapid mixing of the Jerrum-Sinclair Markov chain for sampling almost uniformly from the set of perfect and near perfect matchings of a given graph. In particular, we show that there exists a bipartite graph G such that any Markovian coupling argument on the Jerrum-Sinclair Markov chain for G must necessarily take time exponential in the number ... View full abstract»

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  • A probabilistic algorithm for k-SAT and constraint satisfaction problems

    Publication Year: 1999, Page(s):410 - 414
    Cited by:  Papers (30)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (84 KB)

    We present a simple probabilistic algorithm for solving k-SAT and more generally, for solving constraint satisfaction problems (CSP). The algorithm follows a simple local search paradigm (S. Minton et al., 1992): randomly guess an initial assignment and then, guided by those clauses (constraints) that are not satisfied, by successively choosing a random literal from such a clause and flipping the ... View full abstract»

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  • Random walks on truncated cubes and sampling 0-1 knapsack solutions

    Publication Year: 1999, Page(s):230 - 240
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (188 KB)

    We solve an open problem concerning the mixing time of a symmetric random walk on an n-dimensional cube truncated by a hyperplane, showing that it is polynomial in n. As a consequence, we obtain a full-polynomial randomized approximation scheme for counting the feasible solutions of a 0-1 knapsack problem. The key ingredient in our analysis is a combinatorial construction we call a “balanced... View full abstract»

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  • Improved bounds for sampling colorings

    Publication Year: 1999, Page(s):51 - 59
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (144 KB)

    We consider the problem of sampling uniformly from the set of proper k-colorings of a graph with maximum degree Δ. Our main result is the design Markov chain that converges in O(nk log n) time to the desired distribution when k>11/6 Δ View full abstract»

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  • Cuts, trees and l1-embeddings of graphs

    Publication Year: 1999, Page(s):399 - 408
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (188 KB)

    Motivated by many recent algorithmic applications, the paper aims to promote a systematic study of the relationship between the topology of a graph and the metric distortion incurred where the graph is embedded into l1 space. The main results are: 1. Explicit constant-distortion embeddings of all series parallel graphs, and all graphs with bounded Euler number. These are thus the first ... View full abstract»

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  • Torpid mixing of some Monte Carlo Markov chain algorithms in statistical physics

    Publication Year: 1999, Page(s):218 - 229
    Cited by:  Papers (8)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (208 KB)

    Studies two widely used algorithms, Glauber dynamics and the Swendsen-Wang (1987) algorithm, on rectangular subsets of the hypercubic lattice Zd. We prove that, under certain circumstances, the mixing time in a box of side length L with periodic boundary conditions can be exponential in Ld-1. In other words, under these circumstances, the mixing in these widely used algorithm... View full abstract»

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  • Edge-disjoint routing in plane switch graphs in linear time

    Publication Year: 1999, Page(s):330 - 339
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (216 KB)

    By a switch graph we mean an undirected graph G=(P∪˙W,E) such that all vertices in P (the plugs) have degree one and all vertices in W (the switches) have even degrees. We call G plane if G is planar and can be embedded such that all plugs are in the outer face. Given a set (s1,t1), ..., (sk,tk) of pairs of plugs, the problem is to find edge-disj... View full abstract»

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  • A 5/2n2-lower bound for the rank of n×n-matrix multiplication over arbitrary fields

    Publication Year: 1999, Page(s):45 - 50
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (124 KB)

    We prove a lower bound of 5/2n2-3n for the rank of n×n-matrix multiplication over an arbitrary field. Similar bounds hold for the rank of the multiplication in noncommutative division algebras and for the multiplication of upper triangular matrices View full abstract»

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  • Lovasz's lemma for the three-dimensional K-level of concave surfaces and its applications

    Publication Year: 1999, Page(s):389 - 398
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (208 KB)

    We show that for any line l in space, there are at most k(k+1) tangent planes through l to the k-level of an arrangement of concave surfaces. This is a generalization of L. Lovasz's (1971) lemma, which is a key constituent in the analysis of the complexity of k-level of planes. Our proof is constructive, and finds a family of concave surfaces covering the “laminated at-most-k level”. A... View full abstract»

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  • On counting independent sets in sparse graphs

    Publication Year: 1999, Page(s):210 - 217
    Cited by:  Papers (11)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (132 KB)

    We prove two results concerning approximate counting of independent sets in graphs with constant maximum degree Δ. The first result implies that the Monte-Carlo Markov chain technique is likely to fail if Δ⩾6. The second shows that no fully polynomial randomized approximation scheme can exist for Δ⩾25, unless P=NP under randomized reductions View full abstract»

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  • Satisfiability of word equations with constants is in PSPACE

    Publication Year: 1999, Page(s):495 - 500
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (108 KB)

    We prove that the satisfiability problem for word equations is in PSPACE. The satisfiability problem for word equations has a simple formulation: find out whether or not an input word equation has a solution. The decidability of the problem was proved by G.S. Makanin (1977). His decision procedure is one of the most complicated algorithms existing in the literature. We propose an alternative algor... View full abstract»

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  • Taking a walk in a planar arrangement

    Publication Year: 1999, Page(s):100 - 110
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (172 KB)

    We present a randomized algorithm for computing portions of an arrangement of n arcs in the plane, each pair of which intersect in at most t points. We use this algorithm to perform online walks inside such an arrangement (i.e., compute all the faces that a curve, given in an online manner, crosses), and to compute a level in an arrangement, both in an output-sensitive manner. The expected running... View full abstract»

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  • Finding double Euler trails of planar graphs in linear time [CMOS VLSI circuit design]

    Publication Year: 1999, Page(s):319 - 329
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (220 KB)

    The paper answers an open question in the design of complimentary metal-oxide semiconductor (CMOS) VLSI circuits. It asks whether a polynomial-time algorithm can decide if a given planar graph has a plane embedding ε such that ε has a Euler trail P=e1e 2...em and its dual graph has a Euler trail P*=e 1*e2*...em* where e View full abstract»

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  • Improved combinatorial algorithms for the facility location and k-median problems

    Publication Year: 1999, Page(s):378 - 388
    Cited by:  Papers (65)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (164 KB)

    We present improved combinatorial approximation algorithms for the uncapacitated facility location and k-median problems. Two central ideas in most of our results are cost scaling and greedy improvement. We present a simple greedy local search algorithm which achieves an approximation ratio of 2.414+ε in O˜(n2/ε) time. This also yields a bicriteria approximation tradeoff... View full abstract»

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  • Primality and identity testing via Chinese remaindering

    Publication Year: 1999, Page(s):202 - 208
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (136 KB)

    Gives a simple and new primality testing algorithm by reducing primality testing for a number n to testing if a specific univariate identity over Zn holds. We also give new randomized algorithms for testing if a multivariate polynomial, over a finite field or over rationals, is identically zero. The first of these algorithms also works over Zn for any n. The running time of t... View full abstract»

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  • Hardness of approximating Σ2p minimization problems

    Publication Year: 1999, Page(s):465 - 474
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (132 KB)

    We show that a number of natural optimization problems in the second level of the Polynomial Hierarchy are Σ2p -hard to approximate to within nε factors, for specific ε>0. The main technical tool is the use of explicit dispersers to achieve strong, direct inapproximability results. The problems we consider include Succinct Set Cover, Minimum Equi... View full abstract»

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