# Proceedings of 37th Conference on Foundations of Computer Science

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• ### Proceedings of 37th Conference on Foundations of Computer Science

Publication Year: 1996
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• ### Approximate strip packing

Publication Year: 1996, Page(s):31 - 36
Cited by:  Papers (10)
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We present an approximation scheme for strip-packing, or packing rectangles into a rectangle of fixed width and minimum height, a classical NP-hard cutting-stock problem. The algorithm finds a packing of n rectangles whose total height is within a factor of (1+/spl epsiv/) of optimal, and has running time polynomial both in n and in 1//spl epsiv/. It is based on a reduction to fractional bin-packi... View full abstract»

• ### Author index

Publication Year: 1996
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• ### Computing vertex connectivity: new bounds from old techniques

Publication Year: 1996, Page(s):462 - 471
Cited by:  Papers (4)
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The vertex connectivity κ of a graph is the smallest number of vertices whose deletion separates the graph or makes it trivial. We present the fastest known deterministic algorithm for finding the vertex connectivity and a corresponding separator. The time for a digraph having n vertices and m edges is O(min{κ3+n,κn}m); for an undirected graph the term m can be replace... View full abstract»

• ### All pairs almost shortest paths

Publication Year: 1996, Page(s):452 - 461
Cited by:  Papers (4)
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Let G=(V,E) be an unweighted undirected graph on n vertices. A simple argument shows that computing all distances in G with an additive one-sided error of at most 1 is as hard as Boolean matrix multiplication. Building on recent work of D. Aingworth et al. (1996), we describe an O˜(min{n3/2m1/2,n7/3 }) time algorithm APASP2 for computing all distan... View full abstract»

• ### Static dictionaries on AC0 RAMs: query time &thetas;(√log n/log log n) is necessary and sufficient

Publication Year: 1996, Page(s):441 - 450
Cited by:  Papers (1)
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In this paper we consider solutions to the static dictionary problem on AC0 RAMs, i.e. random access machines where the only restriction on the finite instruction set is that all computational instructions are in AC0. Our main result is a tight upper and lower bound of θ(√log n/log log n) on the time for answering membership queries in a set of size n when reasona... View full abstract»

• ### Equivalence in finite-variable logics is complete for polynomial time

Publication Year: 1996, Page(s):264 - 273
Cited by:  Papers (2)
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How difficult is it to decide whether two finite structures can be distinguished in a given logic? For first order logic, this question is equivalent to the graph isomorphism problem with its well-known complexity theoretic difficulties. Somewhat surprisingly, the situation is much clearer when considering the fragments Lk of first-order logic whose formulae contain at most k (free or b... View full abstract»

• ### Potential of the approximation method

Publication Year: 1996, Page(s):431 - 440
Cited by:  Papers (4)
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Developing some techniques for the approximation method, we establish precise versions of the following statements concerning lower bounds for circuits that detect cliques of size s in a graph with m vertices. For 5⩽s⩽m/4, a monotone circuit computing CLIQUE(m, s) contains at least (1/2) 1.8min(√s-12,m/(4s))/ gates. If a non-monotone circuit computes CLIQUE using a “... View full abstract»

• ### Near-optimal parallel prefetching and caching

Publication Year: 1996, Page(s):540 - 549
Cited by:  Papers (8)  |  Patents (1)
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The authors consider algorithms for integrated prefetching and caching in a model with a fixed-size cache and any number of backing storage devices (disks). Previously, the single disk case was considered by Cao et al. (1995). They show that the natural extension of their aggressive algorithm to the parallel disk case is suboptimal by a factor near the number of disks in the worst case. The main r... View full abstract»

• ### Temporal logic and semidirect products: an effective characterization of the until hierarchy

Publication Year: 1996, Page(s):256 - 263
Cited by:  Papers (4)
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We reveal an intimate connection between semidirect products of finite semigroups and substitution of formulas in linear temporal logic. We use this connection to obtain an algebraic characterization of the until' hierarchy of linear temporal logic; the k-th level of that hierarchy is comprised of all temporal properties that are expressible by a formula of nesting depth at most k in the until' ... View full abstract»

• ### The Boolean isomorphism problem

Publication Year: 1996, Page(s):422 - 430
Cited by:  Papers (5)  |  Patents (1)
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We investigate the computational complexity of the Boolean isomorphism problem (BI): on input of two Boolean formulas F and G decide whether there exists a permutation of the variables of G such that F and G become equivalent. Our main result is a one-round interactive proof for BI, where the verifier has access to an NP oracle. To obtain this, we use a recent result from learning theory by N. Bsh... View full abstract»

• ### Universal data compression and portfolio selection

Publication Year: 1996, Page(s):534 - 538
Cited by:  Papers (5)  |  Patents (1)
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The authors consider universal data compression, universal portfolio selection (online portfolio algorithms) and the relationship of both to information theory. Apparently the fundamental minimax redundancy game in data compression and the minimax regret game for the growth rate of wealth in investment have the same answer. There is also a duality between entropy rate and the growth rate of wealth View full abstract»

• ### The regularity lemma and approximation schemes for dense problems

Publication Year: 1996, Page(s):12 - 20
Cited by:  Papers (20)
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There are two main contributions of the present paper. In the first, we use the constructive version of the Regularity Lemma to give directly simple polynomial time approximation schemes for several graph “subdivision” problems in dense graphs including the Max Cut problem, the Graph Bisection problem, the Min l-way cut problem and Graph Separator problem. Arora, Karger and Karpinski (... View full abstract»

• ### Approximate option pricing

Publication Year: 1996, Page(s):244 - 253
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As increasingly large volumes of sophisticated options are traded in world financial markets, determining a “fair” price for these options has become an important and difficult computational problem. Many valuation codes use the binomial pricing model, in which the stock price is driven by a random walk. In this model, the value of an n-period option on a stock is the expected time-dis... View full abstract»

• ### Discrepancy sets and pseudorandom generators for combinatorial rectangles

Publication Year: 1996, Page(s):412 - 421
Cited by:  Papers (6)
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A common subproblem of DNF approximate counting and derandomizing RL is the discrepancy problem for combinatorial rectangles. We explicitly construct a poly(n)-size sample space that approximates the volume of any combinatorial rectangle in [n]n to within o(1) error. The construction extends the previous techniques for the analogous hitting set problem, most notably via discrepancy pres... View full abstract»

• ### Maximum likelihood decoding of Reed Solomon codes

Publication Year: 1996, Page(s):164 - 172
Cited by:  Papers (3)  |  Patents (2)
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We present a randomized algorithm which takes as input n distinct points {(xi,yi)}i=1n from F×F (where F is a field) and integer parameters t and d and returns a list of all univariate polynomials f over F in the variable a of degree at most d which agree with the given set of points in at least t places (i.e., yi=f(xi) for at... View full abstract»

• ### The geometry of coin-weighing problems

Publication Year: 1996, Page(s):524 - 532
Cited by:  Papers (2)
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Given a set of m coins out of a collection of coins of k unknown distinct weights, the authors wish to decide if all the m given coins have the same weight or not using the minimum possible number of weighings in a regular balance beam. Let m(n,k) denote the maximum possible number of coins for which the above problem can be solved in n weighings. They show that m(n,2)=n(½+o(1))n... View full abstract»

• ### Median selection requires (2+ϵ)n comparisons

Publication Year: 1996, Page(s):125 - 134
Cited by:  Papers (1)
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Improving a long standing result of Bent and John (1985), we obtain a (2+ε)n lower bound (for some fixed ε>0) on the number of comparisons required, in the worst case, for selecting the median of n elements. The new lower bound is obtained using a weight function that allows us to combine leaf counting and adversary arguments View full abstract»

• ### Polynomial time approximation schemes for Euclidean TSP and other geometric problems

Publication Year: 1996, Page(s):2 - 11
Cited by:  Papers (44)  |  Patents (1)
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We present a polynomial time approximation scheme for Euclidean TSP in ℜ2. Given any n nodes in the plane and ε>0, the scheme finds a (1+ε)-approximation to the optimum traveling salesman tour in time n0(1/ε). When the nodes are in ℜd, the running time increases to n(O˜(logd-2n)/εd-1) The previous best appr... View full abstract»

• ### Efficient information gathering on the Internet

Publication Year: 1996, Page(s):234 - 243
Cited by:  Papers (9)
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The Internet offers unprecedented access to information. At present most of this information is free, but information providers ore likely to start charging for their services in the near future. With that in mind this paper introduces the following information access problem: given a collection of n information sources, each of which has a known time delay, dollar cost and probability of providin... View full abstract»

• ### Load balancing and density dependent jump Markov processes

Publication Year: 1996, Page(s):213 - 222
Cited by:  Papers (18)  |  Patents (1)
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We provide a new approach for analyzing both static and dynamic randomized load balancing strategies. We demonstrate the approach by providing the first analysis of the following model: customers arrive as a Poisson stream of rate λn, λ<1, at a collection of n servers. Each customer chooses some constant d servers independently and uniformly at random from the n servers... View full abstract»

• ### Single-source unsplittable flow

Publication Year: 1996, Page(s):68 - 77
Cited by:  Papers (33)
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The max-flow min-cut theorem of Ford and Fulkerson is based on an even more foundational result, namely Menger's theorem on graph connectivity Menger's theorem provides a good characterization for the following single-source disjoint paths problem: given a graph G, with a source vertex s and terminals t1,...,tk, decide whether there exist edge-disjoint s-ti paths f... View full abstract»

• ### Path coloring on the mesh

Publication Year: 1996, Page(s):400 - 409
Cited by:  Papers (9)
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In the minimum path coloring problem, we are given a list of pairs of vertices of a graph. We are asked to connect each pair by a colored path. Paths of the same color must be edge disjoint. Our objective is to minimize the number of colors used. This problem was raised by A. Aggarwal et al. (1994) and P. Raghavan and E. Upfal (1994) as a model for routing in all-optical networks. It is also relat... View full abstract»

• ### Factoring graphs to bound mixing rates

Publication Year: 1996, Page(s):194 - 203
Cited by:  Papers (2)
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This paper develops a new technique for bounding the mixing rate of a Markov chain by decomposing the state space into factors. The first application is an efficient Monte Carlo Markov chain algorithm for generating random three-colorings of 2-dimensional lattice regions. This provides a rigorous tool for studying some properties of the 3-state Potts model and the ice model from statistical mechan... View full abstract»

• ### Highly fault-tolerant parallel computation

Publication Year: 1996, Page(s):154 - 163
Cited by:  Papers (26)
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We re-introduce the coded model of fault-tolerant computation in which the input and output of a computational device are treated as words in an error-correcting code. A computational device correctly computes a function in the coded model if its input and output, once decoded, are a valid input and output of the function. In the coded model, it is reasonable to hope to simulate all computational ... View full abstract»