Sökning: "mixture theory"

Visar resultat 11 - 15 av 146 avhandlingar innehållade orden mixture theory.

1. 11. Estimation of Nonlinear Latent Variable and Mixture Models

   Författare :Johan Vegelius; Shaobo Jin; Fan Yang-Wallentin; Melanie Wall; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; structural equation modeling; semiparametric; EM algorithm; adaptive Gauss-Hermite quadrature approximation; Laplace approximation; zero inflation; Statistics; Statistik;

   Sammanfattning : In this thesis methods are developed for estimation of latent variable models. In particular nonlinear structural equation models are estimated in the presence of ordinal data and mixture models for count data. LÄS MER

3. 12. Statistical methods in medical image estimation and sparse signal recovery

   Författare :Fekadu Lemessa Bayisa; Jun Yu; Ottmar Cronie; Henning Omre; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Computed tomography; magnetic resonance imaging; Gaussian mixture model; skew-Gaussian mixture model; hidden Markov random field; hidden Markov model; supervised statistical learning; synthetic CT images; pseudo-CT images; spike and slab prior; adaptive algorithm;

   Sammanfattning : This thesis presents work on methods for the estimation of computed tomography (CT) images from magnetic resonance (MR) images for a number of diagnostic and therapeutic workflows. The study also demonstrates sparse signal recovery method, which is an intermediate method for magnetic resonance image reconstruction. LÄS MER

4. 13. Kontraktsstyrning i teori och praktik

   Författare :Karin Bryntse; Företagsekonomiska institutionen; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Management of enterprises; hierarchy; market; interorganisational theory; governance structure; Contract management; public procurement; Företagsledning; management;

   Sammanfattning : The general aim of this thesis is to develop an increased understanding of contract management as a mode of governance. A specific aim has been to explore how complex municipal services are managed by contract. LÄS MER

5. 14. Bayesian Cluster Analysis : Some Extensions to Non-standard Situations

   Författare :Jessica Franzén; Daniel Thorburn; Jukka Corander; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cluster analysis; Clustering; Classification; Mixture model; Gaussian; Bayesian inference; MCMC; Gibbs sampler; Deviant group; Longitudinal; Missing data; Multiple imputation; Statistics; Statistik; Statistics; statistik;

   Sammanfattning : The Bayesian approach to cluster analysis is presented. We assume that all data stem from a finite mixture model, where each component corresponds to one cluster and is given by a multivariate normal distribution with unknown mean and variance. LÄS MER

7. 15. Quantitative methods for diffusion measurements in fluorescence microscopy

   Författare :Marco Longfils; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cross-validation.; single particle tracking; Confocal laser scanning microscopy; raster scan; correlation spectroscopy; mixture models; diffusion;

   Sammanfattning : In this work, statistical methods are developed for mapping mass transport locally based on images collected using a confocal laser scanning microscope. Besides presenting raster image correlation spectroscopy as an established method in fluorescence microscopy, we introduce a single particle tracking method which takes advantage of the raster scanning of the image in a confocal microscope. LÄS MER