An optimal algorithm for approximate nearest neighbor searching fixed dimensions

S Arya, DM Mount, NS Netanyahu… - Journal of the ACM …, 1998 - dl.acm.org
S Arya, DM Mount, NS Netanyahu, R Silverman, AY Wu
Journal of the ACM (JACM), 1998dl.acm.org
Consider a set of S of n data points in real d-dimensional space, Rd, where distances are
measured using any Minkowski metric. In nearest neighbor searching, we preprocess S into
a data structure, so that given any query point q∈ Rd, is the closest point of S to q can be
reported quickly. Given any positive real ϵ, data point p is a (1+ ϵ)-approximate nearest
neighbor of q if its distance from q is within a factor of (1+ ϵ) of the distance to the true
nearest neighbor. We show that it is possible to preprocess a set of n points in Rd in O (dn …
Consider a set of S of n data points in real d-dimensional space, Rd, where distances are measured using any Minkowski metric. In nearest neighbor searching, we preprocess S into a data structure, so that given any query point q∈ Rd, is the closest point of S to q can be reported quickly. Given any positive real ϵ, data point p is a (1 +ϵ)-approximate nearest neighbor of q if its distance from q is within a factor of (1 + ϵ) of the distance to the true nearest neighbor. We show that it is possible to preprocess a set of n points in Rd in O(dn log n) time and O(dn) space, so that given a query point q ∈ Rd, and ϵ > 0, a (1 + ϵ)-approximate nearest neighbor of q can be computed in O(cd, ϵ log n) time, where cd,ϵd ⌈1 + 6d/ϵ⌉d is a factor depending only on dimension and ϵ. In general, we show that given an integer k ≥ 1, (1 + ϵ)-approximations to the k nearest neighbors of q can be computed in additional O(kd log n) time.
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