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

17-19 Oct. 1999

Filter Results

Displaying Results 1 - 25 of 69
  • 40th Annual Symposium on Foundations of Computer Science (Cat. No.99CB37039)

    Publication Year: 1999
    Request permission for commercial reuse | PDF file iconPDF (266 KB)
    Freely Available from IEEE
  • Primal-dual approximation algorithms for metric facility location and k-median problems

    Publication Year: 1999, Page(s):2 - 13
    Cited by:  Papers (42)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (150 KB)

    We present approximation algorithms for the metric uncapacitated facility location problem and the metric k-median problem achieving guarantees of 3 and 6 respectively. The distinguishing feature of our algorithms is their low running time: O(m log m) and O(m log m(L+log(n))) respectively, where n and m are the total number of vertices and edges in the underlying graph. The main algorithmic idea i... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Approximation algorithms for classification problems with pairwise relationships: metric labeling and Markov random fields

    Publication Year: 1999, Page(s):14 - 23
    Cited by:  Papers (25)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (151 KB)

    In a traditional classification problem, we wish to assign one of k labels (or classes) to each of n objects, in a way that is consistent with some observed data that we have about the problem. An active line of research in this area is concerned with classification when one has information about pairwise relationships among the objects to be classified; this issue is one of the principal motivati... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Approximating fractional multicommodity flow independent of the number of commodities

    Publication Year: 1999, Page(s):24 - 31
    Cited by:  Papers (14)  |  Patents (7)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (126 KB)

    We describe fully polynomial time approximation schemes for various multicommodity flow problems in graphs with m edges and n vertices. We present the first approximation scheme for maximum multicommodity flow that is independent of the number of commodities k, and our algorithm improves upon the runtime of previous algorithms by this factor of k, running in O*(/spl epsiv//sup -2/ m/sup 2/) time. ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Approximation schemes for minimizing average weighted completion time with release dates

    Publication Year: 1999, Page(s):32 - 43
    Cited by:  Papers (34)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (195 KB)

    We consider the problem of scheduling n jobs with release dates on m machines so as to minimize their average weighted completion time. We present the first known polynomial time approximation schemes for several variants of this problem. Our results include PTASs for the case of identical parallel machines and a constant number of unrelated machines with and without preemption allowed. Our scheme... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A 5/2n/sup 2/-lower bound for the rank of n/spl times/n-matrix multiplication over arbitrary fields

    Publication Year: 1999, Page(s):45 - 50
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (118 KB)

    We prove a lower bound of 5/2n/sup 2/-3n for the rank of n/spl times/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»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Improved bounds for sampling colorings

    Publication Year: 1999, Page(s):51 - 59
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (137 KB)

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

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A non-linear time lower bound for Boolean branching programs

    Publication Year: 1999, Page(s):60 - 70
    Cited by:  Papers (16)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (177 KB)

    We prove that for all positive integer k and for all sufficiently small /spl epsiv/>0 if n is sufficiently large then there is no Boolean (or 2-way) branching program of size less than 2/sup em/ which for all inputs X/spl sube/{0, 1, ..., n-1} computes in time kn the parity of the number of elements of the set of all pairs (x,y) with the property x/spl isin/X, y/spl isin/X, x<y, x+y/spl isin... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Derandomizing Arthur-Merlin games using hitting sets

    Publication Year: 1999, Page(s):71 - 80
    Cited by:  Papers (13)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (145 KB)

    We prove that AM (and hence Graph Nonisomorphism) is in NP if for some /spl epsiv/>0, some language in NE/spl cap/ coNE requires nondeterministic circuits of size 2/sup en/. This improves results of Arvind and Kobler (1997) and of Klivans and Van Melkebeek (1999) who have proven the same conclusion, but under stronger hardness assumptions, namely, either the existence of a language in NE/spl ca... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Fully dynamic algorithms for maintaining all-pairs shortest paths and transitive closure in digraphs

    Publication Year: 1999, Page(s):81 - 89
    Cited by:  Papers (39)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (133 KB)

    This paper presents the first fully dynamic algorithms for maintaining all-pairs shortest paths in digraphs with positive integer weights less than b. For approximate shortest paths with an error factor of (2+/spl epsiv/), for any positive constant /spl epsiv/, the amortized update time is O(n/sup 2/ log/sup 2/ n/log log n); for an error factor of (1+/spl epsiv/) the amortized update time is O(n/s... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Dynamic planar convex hull operations in near-logarithmic amortized time

    Publication Year: 1999, Page(s):92 - 99
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (189 KB)

    We give a data structure that allows arbitrary insertions and deletions on a planar point set P and supports basic queries on the convex hull of P, such as membership and tangent-finding. Updates take O(log/sup 1+/spl epsiv// n) amortized time and queries take O(log n) time each, where n is the maximum size of P and /spl epsiv/ is any fixed positive constant. For some advanced queries such as brid... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • 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 (167 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»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • PSPACE has constant-round quantum interactive proof systems

    Publication Year: 1999, Page(s):112 - 119
    Cited by:  Papers (7)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (147 KB)

    We introduce quantum interactive proof systems, which are interactive proof systems in which the prover and verifier may perform quantum computations and exchange quantum messages. It is proved that every language in PSPACE has a quantum interactive proof system that requires a total of only three messages to be sent between the prover and verifier and has exponentially small (one-sided) probabili... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Verifiable random functions

    Publication Year: 1999, Page(s):120 - 130
    Cited by:  Papers (37)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (213 KB)

    We efficiently combine unpredictability and verifiability by extending the Goldreich-Goldwasser-Micali (1986) construction of pseudorandom functions f/sub s/ from a secret seed s, so that knowledge of s not only enables one to evaluate f/sub s/ at any point x, but also to provide an NP-proof that the value f/sub s/(x) is indeed correct without compromising the unpredictability of f/sub s/ at any o... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • How asymmetry helps load balancing

    Publication Year: 1999, Page(s):131 - 141
    Cited by:  Papers (19)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (170 KB)

    This paper deals with balls and bins processes related to randomized load balancing, dynamic resource allocation and hashing. Suppose n balls have to be assigned to n bins, where each ball has to be placed without knowledge about the distribution of previously placed balls. The goal is to achieve an allocation that is as even as possible so that no bin gets much more balls than the average. A well... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Noncryptographic selection protocols

    Publication Year: 1999, Page(s):142 - 152
    Cited by:  Papers (19)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (149 KB)

    Selection tasks generalize some well studied problems, such as collective coin flipping and leader election. We present new selection protocols in the full information model, and new negative results. In particular when there are (1+/spl delta/)n/2 good players, we show a protocol that chooses a good leader with probability /spl Omega/(/spl delta//sup 1.65/), and show that every leader election pr... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A sublinear time approximation scheme for clustering in metric spaces

    Publication Year: 1999, Page(s):154 - 159
    Cited by:  Papers (20)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (170 KB)

    The metric 2-clustering problem is defined as follows: given a metric (or weighted graph) (X,d), partition X into two sets S(1) and S(2) in order to minimize the value of /spl Sigma//sub i//spl Sigma//sub {u,v}/spl sub/S(i)/d(u,v). In this paper, we show an approximation scheme for this problem. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Efficient regular data structures and algorithms for location and proximity problems

    Publication Year: 1999, Page(s):160 - 170
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (344 KB)

    Investigates data structures obtained by a recursive partitioning of the input domain into regions of equal size. One of the most well-known examples of such a structure is the quadtree, which is used in this paper as a basis for more complex data structures; we also provide multidimensional versions of the stratified tree of P. van Emde Boas (1997). We show that, under the assumption that the inp... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Approximate nearest neighbor algorithms for Hausdorff metrics via embeddings

    Publication Year: 1999, Page(s):171 - 179
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (236 KB)

    Hausdorff metrics are used in geometric settings for measuring the distance between sets of points. They have been used extensively in areas such as computer vision, pattern recognition and computational chemistry. While computing the distance between a single pair of sets under the Hausdorff metric has been well studied, no results are known for the nearest-neighbor problem under Hausdorff metric... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • 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 ¤Án/, the optimal derandomization is P=BPP. However, for weaker lower bound functions... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Error reduction for extractors

    Publication Year: 1999, Page(s):191 - 201
    Cited by:  Papers (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (185 KB)

    An extractor is a function which extracts (almost) truly random bits from a weak random source, using a small number of additional random bits as a catalyst. We present a general method to reduce the error of any extractor. Our method works particularly well in the case that the original extractor extracts up to a constant function of the source min-entropy and achieves a polynomially small error.... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • 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 (128 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 Z/sub n/ 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 Z/sub n/ for any n. The running time of the algorit... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On counting independent sets in sparse graphs

    Publication Year: 1999, Page(s):210 - 217
    Cited by:  Papers (12)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (125 KB)

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

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Torpid mixing of some Monte Carlo Markov chain algorithms in statistical physics

    Publication Year: 1999, Page(s):218 - 229
    Cited by:  Papers (10)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (203 KB)

    Studies two widely used algorithms, Glauber dynamics and the Swendsen-Wang (1987) algorithm, on rectangular subsets of the hypercubic lattice Z/sup d/. We prove that, under certain circumstances, the mixing time in a box of side length L with periodic boundary conditions can be exponential in L/sup d-1/. In other words, under these circumstances, the mixing in these widely used algorithms is not r... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Random walks on truncated cubes and sampling 0-1 knapsack solutions

    Publication Year: 1999, Page(s):230 - 240
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (181 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 almos... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.