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2004
ACM

Approximate Counts and Quantiles over Sliding Windows

14 years 11 months ago
Approximate Counts and Quantiles over Sliding Windows
We consider the problem of maintaining approximate counts and quantiles over fixed- and variablesize sliding windows in limited space. For quantiles, we present deterministic algorithms whose space requirements are O(1 log 1 log N) and O(1 log 1 log N log N) in the worst-case for fixed- and variablesize windows, respectively, where N denotes the current number of elements in the window. Our space bounds improve upon the previous best bounds of O( 1 2 polylog(1 , N)). For counts, we present both deterministic and randomized algorithms. The deterministic algorithms require O(1 log2 1 ) and O(1 log2 1 log N) worst-case space for fixed- and variable-size windows, respectively, while the randomized ones require O(1 log 1 ) and O(1 log 1 log N) worst-case space. We believe no previous work on space-efficient approximate counts for sliding windows exists.
Arvind Arasu, Gurmeet Singh Manku
Added 08 Dec 2009
Updated 08 Dec 2009
Type Conference
Year 2004
Where PODS
Authors Arvind Arasu, Gurmeet Singh Manku
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