Multi-PQTable for Approximate Nearest-Neighbor Search

Composite Quantization for Approximate Nearest Neighbor Search

This paper presents a novel compact coding approach, composite quantization, for approximate nearest neighbor search. The idea is to use the composition of several elements selected from the dictionaries to accurately approximate a vector and to represent the vector by a short code composed of the indices of the selected elements. To efficiently compute the approximate distance of a query to a ...

Fast Approximate Nearest-Neighbor Search with k-Nearest Neighbor Graph

We introduce a new nearest neighbor search algorithm. The algorithm builds a nearest neighbor graph in an offline phase and when queried with a new point, performs hill-climbing starting from a randomly sampled node of the graph. We provide theoretical guarantees for the accuracy and the computational complexity and empirically show the effectiveness of this algorithm.

Approximate Nearest Neighbor Search in $\ell_p$

We present a new locality sensitive hashing (LSH) algorithm for c-approximate nearest neighbor search in lp with 1 < p < 2. For a database of n points in lp, we achieve O(dn ) query time and O(dn + n) space, where ρ ≤ O((ln c)/c). This improves upon the previous best upper bound ρ ≤ 1/c by Datar et al. (SOCG 2004), and is close to the lower bound ρ ≥ 1/c by O’Donnell, Wu and Zhou (ITCS 2011). T...

Approximate Nearest Neighbor Search Project Report

Hardness of Approximate Nearest Neighbor Search

We prove conditional near-quadratic running time lower bounds for approximate Bichromatic Closest Pair with Euclidean, Manhattan, Hamming, or edit distance. Specifically, unless the Strong Exponential Time Hypothesis (SETH) is false, for every δ > 0 there exists a constant ε > 0 such that computing a (1 + ε)-approximation to the Bichromatic Closest Pair requires Ω (