Sökning: "kernel smoothing"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden kernel smoothing.

1. 1. Continuous-Time Models in Kernel Smoothing

   Författare :Martin Sköld; Matematisk statistik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; deconvolution; errors-in-variables; continuous time; dependent data; bandwidth selection; asymptotic variance; Density estimation; kernel smoothing; size bias.; Mathematics; Matematik;

   Sammanfattning : This thesis consists of five papers (Papers A-E) treating problems in non-parametric statistics, especially methods of kernel smoothing applied to density estimation for stochastic processes (Papers A-D) and regression analysis (Paper E). A recurrent theme is to, instead of treating highly positively correlated data as ``asymptotically independent'', take advantage of local dependence structures by using continuous-time models. LÄS MER

3. 2. Contributions to Kernel Equating

   Författare :Björn Andersson; Fan Yang-Wallentin; Marie Wiberg; Alina A. von Davier; Jorge González; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; observed-score test equating; item response theory; R; equipercentile equating; asymptotic standard errors; non-equivalent groups with anchor test design; Statistics; Statistik;

   Sammanfattning : The statistical practice of equating is needed when scores on different versions of the same standardized test are to be compared. This thesis constitutes four contributions to the observed-score equating framework kernel equating. LÄS MER

4. 3. Efficient Image Retrieval with Statistical Color Descriptors

   Författare :Linh Viet Tran; Reiner Lenz; Björn Kruse; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; color properties; images; statistical; content-based image retrieval CBIR ; non-parametric density estimators; image database; Kernel; Gram-Schmidt; geometry-based; Information technology; Informationsteknologi;

   Sammanfattning : Color has been widely used in content-based image retrieval (CBIR) applications. In such applications the color properties of an image are usually characterized by the probability distribution of the colors in the image. LÄS MER

5. 4. Nonparametric Functional Estimation under Order Restrictions

   Författare :Dragi Anevski; Matematisk statistik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; monotonicity; convexity; deconvolution; kernel smoothing; NPMLE; long range dependence; greatest convex minorant; mixing; Density estimation; limit distribution.; regression; Mathematics; Matematik;

   Sammanfattning : This thesis consists of three papers (Papers A-C) on problems in nonparametric functional estimation, in particular density and regression function estimation and deconvolution, under order assumptions. Pointwise limit distribution results are stated for the obtained estimators, which include isotonic regression estimates, nonparametric maximum likelihood estimates of monotone densities, estimates of convex regression and density functions and deconvolution estimates. LÄS MER

7. 5. Discrete Scale-Space Theory and the Scale-Space Primal Sketch

   Författare :Tony Lindeberg; Jan-Olof Eklundh; Jan. J Koenderink; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Computer vision; low-level processing; scale-space; diffusion; Gaussian filtering; discrete smoothing; primal sketch; segmentation; descriptive elements; scale detection; image structure; focus-of-attention; tuning low-level processing; blob detection; edge detection; edge focusing; histogram analysis; junction classification; perceptual grouping; texture analysis; critical points; classification of blob events; bifurcations; drift velocity; density of local extrema; multi-scale representation; digital signal processing; Computer Science; Datalogi;

   Sammanfattning : This thesis, within the subfield of computer science known as computer vision, deals with the use of scale-space analysis in early low-level processing of visual information. The main contributions comprise the following five subjects:The formulation of a scale-space theory for discrete signals. LÄS MER