Sökning: "spatial statistics"

Visar resultat 36 - 40 av 158 avhandlingar innehållade orden spatial statistics.

1. 36. Spatial inference for non-lattice data using Markov Random fields

   Författare :Linda Werner Hartman; Matematisk statistik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : This thesis deals with how computationally effective lattice models could be used for inference of data with a continuous spatial index. The fundamental idea is to approximate a Gaussian field with a Gaussian Markov random field (GMRF) on a lattice. LÄS MER

3. 37. Local Polynomial Regression with Application on Lidar Measurements

   Författare :Torgny Lindström; Matematisk statistik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik; differential equations; Funktioner; differentialekvationer; variance-function estimation.; spatial dependence; nonparametric; local polynomial regression; local bandwidth selection; lidar; heteroscedasticity; Bivariate estimation; differential absorption; Functions;

   Sammanfattning : This thesis deals with the problem of estimating a function or one of its derivatives from a set of measurements, mainly of a bivariate or spatial nature which is so common in environmental applications. In this work particular attention has been on the lidar (light detection and ranging) application which is a versatile technique for measurement of among other things atmospheric trace gases. LÄS MER

4. 38. 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

5. 39. UNDERSTANDING URBAN PATTERNS Qualitative and Quantitative Approaches

   Författare :Vânia Aparecida Ceccato; KTH; []
   Nyckelord :urban quality; GIS; spatial statistics;

   Sammanfattning : In this thesis, the main field of study is urban patternsand the methodological issues involving the analysis of spatialdata across urban space. Four particular aspects are chosen toillustrate the dynamics of urban space, using Stockholm Countyas case study. LÄS MER

7. 40. Spatial organization of retail activities

   Författare :Helena Nilsson; Johan Klaesson; Sven-Olov Daunfeldt; Özge Öner; Daniel Arribas-Bel; Jönköping University; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES;

   Sammanfattning : This thesis is a compilation of four independent papers that examine the spatial process of retail location. The central question I ask is how changes in access to consumer demand affects retail in terms of size and survival. LÄS MER