A note on quickly finding the nearest neighbour
نویسنده
چکیده
and D dimensional vectors, it takes O (D) operations to compute this distance. For a set of N vectors, computing the nearest neighbour to q would take then O (DN) operations. For large datasets this can be prohibitively expensive. Is there a way to avoid calculating all the distances? This is a large research area (see [2] for a review) and we will focus here on first methods that make use of the triangle inequality for metric distances and secondly a KD-trees which form a spatial data structure.
منابع مشابه
Nearest Neighbour Strategies for Image Understanding
Nearest Neighbour algorithms for pattern recognition have been widely studied. It is now well-established that they offer a quick and reliable method of data classification. In this paper we further develop the basic definition of the standard k-nearest neighbour algorithm to include the ability to resolve conflicts when the highest number of nearest neighbours are found for more than one train...
متن کاملApproximate Nearest-Neighbour Search with Inverted Signature Slice Lists
In this paper we present an original approach for finding approximate nearest neighbours in collections of locality-sensitive hashes. The paper demonstrates that this approach makes high-performance nearest-neighbour searching feasible on Web-scale collections and commodity hardware with minimal degradation in search quality.
متن کاملتأثیر الگوی پراکنش درختان بر برآورد تراکم با روش نمونه برداری نزدیکترین فرد: مطالعات موردی در درختزارهای بنه زاگرس و تودههای شبیه سازی شده
Distance methods and their estimators of density may have biased measurements unless the studied stand of trees has a random spatial pattern. This study aimed at assessing the effect of spatial arrangement of wild pistachio trees on the results of density estimation by using the nearest individual sampling method in Zagros woodlands, Iran, and applying a correction factor based on the spatial p...
متن کاملOn the construction of complete and partial nearest neighbour balanced designs
In this paper, methods for constructing two dimensional nearest neighbour balanced (NNB) designs are considered. The methods given by Afsarinejad and Seeger (1988) are extended to give a new family of nearest neighbour balanced designs. Both nearest neighbour balanced designs with and without borders are constructed. A method of construction of a class of partial nearest neighbour balanced (PNN...
متن کاملA Short Note on Using Multiple Imputation Techniques for Very Small Data Sets
This short note describes a simple experiment to investigate the value of using multiple imputation (MI) methods [2, 3]. We are particularly interested in whether a simple bootstrap based on a k-nearest neighbour (kNN) method can help address the problem of missing values in two very small, but typical, software project data sets. This is an important question because, unfortunately, many real-...
متن کامل