Influence Function of Halfspace Depth
β Scribed by Mario Romanazzi
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 299 KB
- Volume
- 77
- Category
- Article
- ISSN
- 0047-259X
No coin nor oath required. For personal study only.
β¦ Synopsis
The sensitivity of halfspace depth values and contours to perturbations of the underlying distribution is investigated. The influence function of the halfspace depth of any point x # R p is bounded and discontinuous; it is constant and positive when the perturbing observation z is placed in any optimal halfspace and it is constant and negative when z is placed in any non-optimal halfspace. When the optimal halfspace is unique a von Mises expansion allows an easy derivation of the asymptotic distribution of the sample halfspace depth. In the sampling case, in general, addition of a single observation outside the convex hull of the sample alters all the depth regions but only the outer region can be arbitrarily expanded. To obtain the same effect on the inner regions the size of the perturbation is required to be not less than the depth orders. Numerical illustrations of the results are given.
π SIMILAR VOLUMES
In this note we present a characterization of halfspace depth which relates it with well-known concepts of Locational Analysis. This characterization also leads to a natural extension of the concept of depth to noneuclidean location estimation as well as other settings like regression.
Continuity of procedures based on the halfspace (Tukey) depth (location and regression setting) is investigated in the framework of continuity concepts from setvalued analysis. Investigated procedures are depth contours (upper level sets) and maximum depth estimators. Continuity is studied both as t
As the extensions of Tukey's depth, a family of affine invariant depth functions are introduced for multivariate location and dispersion. The location depth functions can be used for the purpose of multivariate ordering. Such kind ordering can retain more information from the original data than that
Radio-frequency-powered glow discharge optical emission spectroscopy (GDOES) is an extremely powerful and reliable technique for depth proΓling analysis of thin, insulating barrier anodic Γlms formed on aluminium. It allows ready and rapid analysis of the Γlms, with depth resolution and sensitivity
The adsorption of atrazine and mecoprop to soil at diΓΎerent levels below the surface was measured and compared with values calculated from the partition coefficient-between soil organic carbon and water-and the carbon content. With soil samples from the top layers, the calculated values were in fair