1416 Oct. 1996
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Proceedings of 37th Conference on Foundations of Computer Science
Publication Year: 1996 PDF (355 KB) 
Approximate strip packing
Publication Year: 1996, Page(s):31  36
Cited by: Papers (11)We present an approximation scheme for strippacking, or packing rectangles into a rectangle of fixed width and minimum height, a classical NPhard cuttingstock 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 binpacki... View full abstract»

Author index
Publication Year: 1996 PDF (99 KB) 
An 8approximation algorithm for the subset feedback vertex set problem
Publication Year: 1996, Page(s):310  319
Cited by: Papers (2)We present an 8approximation algorithm for the problem of finding a minimum weight subset feedback vertex set. The input in this problem consists of an undirected graph G=(V,E) with vertex weights w(v) and a subset of vertices S called special vertices. A cycle is called interesting if it contains at least one special vertex. A subset of vertices is called a subset feedback vertex set with respec... View full abstract»

A 3approximation for the minimum tree spanning k vertices
Publication Year: 1996, Page(s):302  309
Cited by: Papers (16)In this paper we give a 3approximation algorithm for the problem of finding a minimum tree spanning any kvertices in a graph. Our algorithm extends to a 3approximation algorithm for the minimum tour that visits any kvertices View full abstract»

Approximating minimumsize kconnected spanning subgraphs via matching
Publication Year: 1996, Page(s):292  301
Cited by: Papers (4)An efficient heuristic is presented for the problem of finding a minimumsize kconnected spanning subgraph of a given (undirected or directed) graph G=(V,E). There are four versions of the problem, depending on whether G is undirected or directed, and whether the spanning subgraph is required to be knode connected (kNCSS) or kedge connected (kECSS). The approximation guarantees are as follows... View full abstract»

Approximate option pricing
Publication Year: 1996, Page(s):244  253As 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 nperiod option on a stock is the expected timedis... View full abstract»

Deterministic routing with bounded buffers: turning offline into online protocols
Publication Year: 1996, Page(s):370  379
Cited by: Papers (2)In this paper we present a deterministic protocol for routing arbitrary permutations in arbitrary networks. The protocol is analyzed in terms of the size of the network and the routing number of the network. Given a network H of size n, the routing number of H is defined as the maximum over all permutations π on [n] of the minimal number of steps to route π offline in H. We can show that for... View full abstract»

Gadgets, approximation, and linear programming
Publication Year: 1996, Page(s):617  626
Cited by: Papers (8)The authors present a linearprogramming based method for finding “gadgets”, i.e., combinatorial structures reducing constraints of one optimization problem to constraints of another. A key step in this method is a simple observation which limits the search space to a finite one. Using this new method they present a number of new, computerconstructed gadgets for several different redu... View full abstract»

Computationally hard algebraic problems
Publication Year: 1996, Page(s):284  289In this paper we present a simple geometriclike series of elements in a finite field Fq, and show that computing its sum is NPhard. This problem is then reduced to the problem of counting mod p the number of zeroes in a linear recurrence sequence with elements in a finite Fp, where p is a small prime. Hence the latter problem is also NPhard. In the lecture we shall also su... View full abstract»

Solving systems of polynomial congruences modulo a large prime
Publication Year: 1996, Page(s):115  124
Cited by: Papers (2)We consider the following polynomial congruences problem: given a prime p, and a set of polynomials f1,...,fm∈ Fp[x1,...,xn] of total degree at most d, solve the system f1=...=fm=0 for solution(s) in Fpn. We give a randomized algorithm for the decision version of this problem. ... View full abstract»

Efficient information gathering on the Internet
Publication Year: 1996, Page(s):234  243
Cited by: Papers (9)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»

Learning linear transformations
Publication Year: 1996, Page(s):359  368
Cited by: Papers (9)We present a polynomial time algorithm to learn (in Valiant's PAC model) an arbitrarily oriented cube in nspace, given uniformly distributed sample points from it. In fact, we solve the more general problem of learning, in polynomial time, a linear (affine) transformation of a product distribution View full abstract»

Verifying identities
Publication Year: 1996, Page(s):612  616The authors provide an O˜(n2) time randomized algorithm to check whether a given operation f:S×S→S is associative (letting n=S). They prove this performance is optimal (up to polylogarithmic factors) even in case the operation is “cancellative”. No subn3 algorithm was previously known for this task. More generally they give an O(nc )... View full abstract»

Simplified and improved resolution lower bounds
Publication Year: 1996, Page(s):274  282
Cited by: Papers (33)We give simple new lower bounds on the lengths of resolution proofs for the pigeonhole principle and for randomly generated formulas. For random formulas, our bounds significantly extend the range of formula sizes for which nontrivial lower bounds are known. For example, we show that with probability approaching 1, any resolution refutation of a randomly chosen 3CNF formula with at most n6/... View full abstract»

Computing permanents over fields of characteristic 3: where and why it becomes difficult
Publication Year: 1996, Page(s):108  114
Cited by: Papers (3)In this paper we consider the complexity of computing permanents over fields of characteristic 3. We present a polynomial time algorithm for computing per(A) for a matrix A such that the rank rg(AATI)⩽1. On the other hand, we show that existence of a polynomialtime algorithm for computing per(A) for a matrix A such that rg(AATI)⩾2 implies NP=R. As a byproduct we ob... View full abstract»

Optimal dynamic interval management in external memory
Publication Year: 1996, Page(s):560  569
Cited by: Papers (16)  Patents (1)The authors present a space and I/Ooptimal externalmemory data structure for answering stabbing queries on a set of dynamically maintained intervals. The data structure settles an open problem in databases and I/O algorithms by providing the first optimal externalmemory solution to the dynamic interval management problem, which is a special case of 2dimensional range searching and a central p... View full abstract»

Tree data structures for Nbody simulation
Publication Year: 1996, Page(s):224  233
Cited by: Papers (3)In this paper, we study data structures for use in Nbody simulation. We concentrate on the spatial decomposition tree used in particlecluster force evaluation algorithms such as the BarnesHut algorithm. We prove that a kd tree is asymptotically inferior to a spatially balanced tree. We show that the worst case complexity of the force evaluation algorithm using a kd tree is Θ(nlog3<... View full abstract»

The optimal pathmatching problem
Publication Year: 1996, Page(s):78  85
Cited by: Papers (3)We describe a common generalization of the weighted matching problem and the weighted matroid intersection problem. In this context we present results implying the polynomialtime solvability of the two problems. We also use our results to give the first strongly polynomial separation algorithm for the convex hull of matchable sets of a graph, and the first polynomialtime algorithm to compute the... View full abstract»

On the applications of multiplicity automata in learning
Publication Year: 1996, Page(s):349  358
Cited by: Papers (4)The learnability of multiplicity automata has attracted a lot of attention, mainly because of its implications on the learnability of several classes of DNF formulae. The authors further study the learnability of multiplicity automata. The starting point is a known theorem from automata theory relating the number of states in a minimal multiplicity automaton for a function f to the rank of a certa... View full abstract»

Efficient selftesting/selfcorrection of linear recurrences
Publication Year: 1996, Page(s):602  611
Cited by: Papers (1)The authors consider the problem of designing selftesters/selfcorrectors for functions defined by linear recurrences. They present the first complete package of efficient and simple selftesters, selfcorrectors, and resultcheckers for such functions. The results are proved by demonstrating an efficient reduction from this problem to the problem of testing linear functions over certain matrix g... View full abstract»

Universal data compression and portfolio selection
Publication Year: 1996, Page(s):534  538
Cited by: Papers (5)  Patents (1)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»

Equivalence in finitevariable logics is complete for polynomial time
Publication Year: 1996, Page(s):264  273
Cited by: Papers (2)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 wellknown complexity theoretic difficulties. Somewhat surprisingly, the situation is much clearer when considering the fragments Lk of firstorder logic whose formulae contain at most k (free or b... View full abstract»

A general approach to dynamic packet routing with bounded buffers
Publication Year: 1996, Page(s):390  399
Cited by: Papers (1)We prove a sufficient condition for the stability of dynamic packet routing algorithms. Our approach reduces the problem of steady state analysis to the easier and better understood question of static routing. We show that certain high probability and worst case bounds on the quasistatic (finite past) performance of a routing algorithm imply bounds on the performance of the dynamic version of that... View full abstract»

Spectral partitioning works: planar graphs and finite element meshes
Publication Year: 1996, Page(s):96  105
Cited by: Papers (30)  Patents (1)Spectral partitioning methods use the Fiedler vectorthe eigenvector of the secondsmallest eigenvalue of the Laplacian matrixto find a small separator of a graph. These methods are important components of many scientific numerical algorithms and have been demonstrated by experiment to work extremely well. In this paper, we show that spectral partitioning methods work well on boundeddegree plana... View full abstract»