The Value of Multiple Read/Write Streams for Approximating Frequency Moments
نویسندگان
چکیده
منابع مشابه
A The Value of Multiple Read/Write Streams for Approximating Frequency Moments
We consider the read/write streams model, an extension of the standard data stream model in which an algorithm can create and manipulate multiple read/write streams in addition to its input data stream. Like the data stream model, the most important parameter for this model is the amount of internal memory used by such an algorithm. The other key parameters are the number of streams the algorit...
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We will develop algorithms that can approximate Fk by making one pass of the stream and using a small amount of memory o(n+m). Frequency moments have a number of applications. F0 represents the number of distinct elements in the streams (which the FM-sketch from last class estimates using O(log n) space. F1 is the number of elements in the stream m. F2 is used in database optimization engines t...
متن کاملEstimating Frequency Moments of Streams
We will develop algorithms that can approximate Fk by making one pass of the stream and using a small amount of memory o(n+m). Frequency moments have a number of applications. F0 represents the number of distinct elements in the streams (which the FM-sketch from last class estimates using O(log n) space. F1 is the number of elements in the stream m. F2 is used in database optimization engines t...
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ژورنال
عنوان ژورنال: ACM Transactions on Computation Theory
سال: 2012
ISSN: 1942-3454,1942-3462
DOI: 10.1145/2077336.2077339