Search for dissertations about: "missing samples"

Showing result 1 - 5 of 65 swedish dissertations containing the words missing samples.

  2. 1. Two Topics in Survey Methodology : Inference from Nonprobability Samples Using the Double Samples Setup

    Author : Boris Lorenc; Daniel Thorburn; Lars Lyberg; Gösta Forsman; Stockholms universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; response process; establishment surveys; socially distributed cognition; response burden; measurement error; nonprobability samples; web surveys; double samples; propensity scores; model-based estimation; imputation; nonparametric imputation; weighting; Surveying; Lantmäteri;

    Abstract : Modelling the response process in establishment surveys proceeded thus far by adding steps of operational character to the core cognitive steps of the individual cognitive model. Here (Paper 1) a larger unit of the cognitive analysis is posited: that part of the enterprise that is engaged in responding to a survey, consisting of one or more employees, the tools they use and the established practices of record keeping and survey responding. READ MORE

  4. 2. Design and analysis of response selective samples in observational studies

    Author : Maria Grünewald; Ola Hössjer; Keith Humphreys; Marie Reilly; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; ascertainment; missing data; outcome dependent sampling; response selective samples; sequential design; stochastic EM algorithm; Mathematical statistics; Matematisk statistik; Mathematical Statistics; matematisk statistik;

    Abstract : Outcome dependent sampling may increase efficiency in observational studies. It is however not always obvious how to sample efficiently, and how to analyze the resulting data without introducing bias. READ MORE

  5. 3. Particle induced x-ray emission - analysis of biological samples

    Author : Jan Pallon; Kärnfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fysicumarkivet A:1987:Pallon;

    Abstract : [abstract missing].... READ MORE

  6. 4. Precise Image-Based Measurements through Irregular Sampling

    Author : Teo Asplund; Robin Strand; Cris L. Luengo Hendriks; Matthew J. Thurley; Gunilla Borgefors; Hugues Talbot; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; image analysis; image processing; mathematical morphology; irregular sampling; adaptive morphology; missing samples; continuous morphology; path opening.; Computerized Image Processing; Datoriserad bildbehandling;

    Abstract : Mathematical morphology is a theory that is applicable broadly in signal processing, but in this thesis we focus mainly on image data. Fundamental concepts of morphology include the structuring element and the four operators: dilation, erosion, closing, and opening. READ MORE

  7. 5. Fluorine mass balance in wildlife and consumer products : How much organofluorine are we missing?

    Author : Lara Schultes; Jonathan P. Benskin; Michael McLachlan; Jörg Feldmann; Elsie M. Sunderland; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; PFASs; PFOS; fluorine mass balance; organofluorine; EOF; TF; wildlife; consumer products; combustion ion chromatography; high resolution mass spectrometry; suspect screening; Applied Environmental Science; tillämpad miljövetenskap;

    Abstract : Per- and polyfluoroalkyl substances (PFASs) are a class of anthropogenic pollutants. Many PFASs are highly persistent and have been linked to adverse effects in humans. According to latest estimates, there are more than 4700 PFASs in global commerce, which poses immense challenges for environmental monitoring. READ MORE