Locality-sensitive hashing scheme based on dynamic collision counting

Locality-Sensitive Hashing (LSH) and its variants are wellknown methods for solving the c-approximate NN Search problem in high-dimensional space. Traditionally, several LSH functions are concatenated to form a“static”compound hash function for building a hash table. In this paper, we propose to use a base of m single LSH functions to construct “dynamic” compound hash functions, and define a new LSH scheme called Collision Counting LSH (C2LSH). If the number of LSH functions under which a data object o collides with a query object q is greater than a pre-specified collision threhold l, then o can be regarded as a good candidate of c-approximate NN of q. This is the basic idea of C2LSH. Our theoretical studies show that, by appropriately choosing the size of LSH function base m and the collision threshold l, C2LSH can have a guarantee on query quality. Notably, the parameter m is not affected by dimensionality of data objects, which makes C2LSH especially good for high dimen...

• Type: Journal
• Year: 2012
• Where: SIGMOD
• Authors: Junhao Gan, Jianlin Feng, Qiong Fang, Wilfred Ng
• Keywords: Database, Hash Function, Hash Functions, Query Quality, SIGMOD 2012