779 research outputs found

    Communication Efficient Checking of Big Data Operations

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    We propose fast probabilistic algorithms with low (i.e., sublinear in the input size) communication volume to check the correctness of operations in Big Data processing frameworks and distributed databases. Our checkers cover many of the commonly used operations, including sum, average, median, and minimum aggregation, as well as sorting, union, merge, and zip. An experimental evaluation of our implementation in Thrill (Bingmann et al., 2016) confirms the low overhead and high failure detection rate predicted by theoretical analysis

    A note on Probably Certifiably Correct algorithms

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    Many optimization problems of interest are known to be intractable, and while there are often heuristics that are known to work on typical instances, it is usually not easy to determine a posteriori whether the optimal solution was found. In this short note, we discuss algorithms that not only solve the problem on typical instances, but also provide a posteriori certificates of optimality, probably certifiably correct (PCC) algorithms. As an illustrative example, we present a fast PCC algorithm for minimum bisection under the stochastic block model and briefly discuss other examples

    On Algebraic Decoding of qq-ary Reed-Muller and Product-Reed-Solomon Codes

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    We consider a list decoding algorithm recently proposed by Pellikaan-Wu \cite{PW2005} for qq-ary Reed-Muller codes RMq(,m,n)\mathcal{RM}_q(\ell, m, n) of length nqmn \leq q^m when q\ell \leq q. A simple and easily accessible correctness proof is given which shows that this algorithm achieves a relative error-correction radius of τ(1qm1/n)\tau \leq (1 - \sqrt{{\ell q^{m-1}}/{n}}). This is an improvement over the proof using one-point Algebraic-Geometric codes given in \cite{PW2005}. The described algorithm can be adapted to decode Product-Reed-Solomon codes. We then propose a new low complexity recursive algebraic decoding algorithm for Reed-Muller and Product-Reed-Solomon codes. Our algorithm achieves a relative error correction radius of τi=1m(1ki/q)\tau \leq \prod_{i=1}^m (1 - \sqrt{k_i/q}). This technique is then proved to outperform the Pellikaan-Wu method in both complexity and error correction radius over a wide range of code rates.Comment: 5 pages, 5 figures, to be presented at 2007 IEEE International Symposium on Information Theory, Nice, France (ISIT 2007

    Secret Sharing Based on a Hard-on-Average Problem

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    The main goal of this work is to propose the design of secret sharing schemes based on hard-on-average problems. It includes the description of a new multiparty protocol whose main application is key management in networks. Its unconditionally perfect security relies on a discrete mathematics problem classiffied as DistNP-Complete under the average-case analysis, the so-called Distributional Matrix Representability Problem. Thanks to the use of the search version of the mentioned decision problem, the security of the proposed scheme is guaranteed. Although several secret sharing schemes connected with combinatorial structures may be found in the bibliography, the main contribution of this work is the proposal of a new secret sharing scheme based on a hard-on-average problem, which allows to enlarge the set of tools for designing more secure cryptographic applications

    A Simple Algorithm for Hamiltonicity

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    We develop a new algebraic technique that solves the following problem: Given a black box that contains an arithmetic circuit ff over a field of characteristic 22 of degree~dd. Decide whether ff, expressed as an equivalent multivariate polynomial, contains a multilinear monomial of degree dd. This problem was solved by Williams \cite{W} and Bj\"orklund et. al. \cite{BHKK} for a white box (the circuit is given as an input) that contains arithmetic circuit. We show a simple black box algorithm that solves the problem with the same time complexity. This gives a simple randomized algorithm for the simple kk-path problem for directed graphs of the same time complexity\footnote{O(f(k))O^*(f(k)) is O(poly(n)f(k))O(poly(n)\cdot f(k))} O(2k)O^*(2^k) as in \cite{W} and with reusing the same ideas from \cite{BHKK} with the above gives another algorithm (probably not simpler) for undirected graphs of the same time complexity O(1.657k)O^*(1.657^k) as in \cite{B10,BHKK}
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