Instructor : Chandra Chekuri Scribe : Chandra Chekuri 1 Estimating Frequency Moments in Streams
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چکیده
A significant fraction of streaming literature is on the problem of estimating frequency moments. Let σ = a1, a2, . . . , am be a stream of numbers where for each i, ai is an intger between 1 and n. We will try to stick to the notation of using m for the length of the stream and n for range of the integers1. Let fi be the number of occurences (or frequency) of integer i in the stream. We let f = (f1, f2, . . . , fn) be the frequency vector for a given stream σ. For k ≥ 0, Fk(σ) is defined to be the k’th frequency moment of σ: Fk = ∑
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Chandra Chekuri (Dept. of Computer Science, University of Illinois at Urbana-Champaign, Urbana, IL), Joseph Cheriyan (Dept. of Combinatorics and Optimization, University of Waterloo, Waterloo, ON), Ryan O’Donnell (School of Computer Science, Carnegie Mellon University, Pittsburgh, PA), Mohammad R. Salavatipour (Dept. of Computing Science, University of Alberta, Edmonton, AL), David Williamson (...
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تاریخ انتشار 2014