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Randomness is Linear in Space
We show that any randomized algorithm that runs in spaceSand timeTand uses poly(S) random bits can be simulated using onlyO(S). Expand
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Linear degree extractors and the inapproximability of max clique and chromatic number
We use our dispersers to derandomize results of Hastad [23] and Feige-Kilian [19] and show that for all ε>0, approximating MAX CLIQUE and CHROMATIC NUMBER to within n1-ε are NP-hard. Expand
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An XOR-based erasure-resilient coding scheme
An (m; n; b; r)-erasure-resilient coding scheme consists of an encoding algorithm and a decoding algorithm with the following properties. The encoding algorithm produces a set of n packets eachExpand
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Optimal speedup of Las Vegas algorithms
The authors describe a simple universal strategy S/sup univ/, with the property that, for any algorithm A, T(A,S) is the best performance that can be achieved, up to a constant factor, by any universal strategy. Expand
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Loss-less condensers, unbalanced expanders, and extractors
An extractor is a procedure which extracts randomness from a random source using a few additional random bits. Expand
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How to recycle random bits
It is shown that modified versions of the linear congruential generator and the shift register generator are provably good for amplifying the correctness of a probabilistic algorithm. Expand
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Randomness-optimal oblivious sampling
We present the first efficient oblivious sampler that uses an optimal number of random bits, up to an arbitrary constant factor bigger than 1. Expand
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Optimal Speedup of Las Vegas Algorithms
A is a Las Vegas algorithm, i.e., A is a randomized algorithm that always produces the correct answer when it stops but whose running time is a random variable. Expand
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Computing with very weak random sources
For any fixed /spl epsiv/>0, we show how to simulate RP algorithms in time n/sup O(log n/) using the output of a /spl delta/-source with min-entropy R/sup /spl Omega/(1/), which is optimal. Expand
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Deterministic Extractors for Bit-Fixing Sources and Exposure-Resilient Cryptography
We give an efficient deterministic algorithm that extracts almost-random bits from sources where $n^{\frac{1}{2}+\gamma} of the $n$ bits are uniformly random and the rest are fixed in advance. Expand
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