Lecture 17: Randomness Extractors
نویسندگان
چکیده
This lecture is about randomness extractors. Extractors are functions that map samples from a non-uniform distribution to samples that are close to being uniformly distributed. The length of the output will in general be smaller than the length of the input of the extractor. The input distribution of the extractor is called the source. A source is a random variable which maps text values to bit strings. The goal is to extract randomness from such sources. Definition 1. Let (Ω, p) be probability space, that is, Ω is a finite set and p ∈ [0, 1]Ω is a vector with ‖p‖1 = 1. A source X over {0, 1}n is a {0, 1}n-valued random variable over some space (Ω, p), that is, a function X : Ω → {0, 1} .
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