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Please use this identifier to cite or link to this item: http://hdl.handle.net/1903/4299

Title: Space-Time Tradeoffs for Approximate Spherical Range Counting
Authors: Arya, Sunil
Malamatos, Theocharis
Mount, David M.
Type: Technical Report
Issue Date: 13-Nov-2006
Series/Report no.: UM Computer Science Department
CS-TR-4842
UMIACS
UMIACS-TR-2006-57
Abstract: We present space-time tradeoffs for approximate spherical range counting queries. Given a set S of n data points in real d-dimensional space along with a positive approximation factor eps, the goal is to preprocess the points so that, given any Euclidean ball B, we can return the number of points of any subset of S that contains all the points within a (1-eps)-factor contraction of B, but contains no points that lie outside a (1+eps)-factor expansion of B. In many applications of range searching it is desirable to offer a tradeoff between space and query time. We present here the first such tradeoffs for approximate range counting queries. Given positive eps and a parameter g, where 2 <= g <= 1/eps, we show how to construct a data structure of space O(n g^d log(1/eps)) that allows us to answer eps-approximate spherical range counting queries in time O(log(ng) + 1/(eps g)^{d-1}). The data structure can be built in time O(n g^d log(n/eps) log(1/eps)). Here n, eps, and g are asymp...
URI: http://hdl.handle.net/1903/4299
Appears in Collections:Technical Reports from UMIACS
Technical Reports of the Computer Science Department

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