We propose simple and fast methods based on nearest neighbors that order objects from high-dimensional data sets from typical points to untypical points. On the one hand, we show that these easy-to-compute orderings allow us to detect outliers (i.e. very untypical points) with a performance comparable to or better than other often much more sophisticated methods. On the other hand, we show how ...

This paper describes an algorithm to compute the envelope of a set of points in a plane, which generates convex or non-convex hulls that represent the area occupied by the given points. The proposed algorithm is based on a k-nearest neighbours approach, where the value of k, the only algorithm parameter, is used to control the “smoothness” of the final solution. The obtained results show that t...

Color space transformation using a 3D lookup table (LUT) with interpolation is used to correlate the source and destination color values in the lattice points of a 3D table, where nonlattice points are interpolated by using the nearest lattice points. This method has been used in many applications with quite satisfactory results, and incorporated into the ICC profile standard.1 In this chapter,...

The problem of finding clusters in data is challenging when clusters are of widely differing sizes, densities and shapes, and when the data contains large amounts of noise and outliers. Many of these issues become even more significant when the data is of very high dimensionality, such as text or time series data. In this paper we present a novel clustering technique that addresses these issues...