Sökning: "Poisson sampling"

Visar resultat 1 - 5 av 18 avhandlingar innehållade orden Poisson sampling.

  1. 1. On unequal probability sampling designs

    Författare :Anton Grafström; Lennart Bondesson; Sara De Luna; Imbi Traat; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; conditional Poisson sampling; correlated Poisson sampling; entropy; extended Sampford sampling; Horvitz-Thompson estimator; inclusion probabilities; list-sequential sampling; non-rejective implementation; Pareto sampling; Poisson sampling; probability functions; ratio estimator; real-time sampling; repeated Poisson sampling; Sampford sampling; sampling designs; splitting method; unequal probability sampling; Mathematical statistics; Matematisk statistik; Mathematical Statistics; matematisk statistik;

    Sammanfattning : The main objective in sampling is to select a sample from a population in order to estimate some unknown population parameter, usually a total or a mean of some interesting variable. When the units in the population do not have the same probability of being included in a sample, it is called unequal probability sampling. LÄS MER

  3. 2. Contributions to the theory of unequal probability sampling

    Författare :Anders Lundquist; Lennart Bondesson; Aleksandras Plikusas; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; balanced sampling; conditional Poisson sampling; inclusion probabilities; maximum entropy; Markov chain Monte Carlo; Pareto sampling; Sampford sampling; unequal probability sampling.; Mathematical statistics; Matematisk statistik; Mathematical Statistics; matematisk statistik;

    Sammanfattning : This thesis consists of five papers related to the theory of unequal probability sampling from a finite population. Generally, it is assumed that we wish to make modelassisted inference, i.e. the inclusion probability for each unit in the population is prescribed before the sample is selected. LÄS MER

  4. 3. Techniques to Calculate Exact Inclusion Probabilities for Conditional Poisson Sampling and Pareto .pi.ps Sampling Designs

    Författare :Nibia Aires; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; sampling theory; conditional Poisson sampling; Pareto pips sampling; order sampling; numerical integration; algorithms; sampling theory;

    Sammanfattning : This thesis consists of five papers and treats two finite population sampling methods, viz. the Conditional Poisson and the Pareto .pi.ps sampling schemes. LÄS MER

  5. 4. The PET sampling puzzle : intelligent data sampling methods for positron emission tomography

    Författare :Klara Leffler; Jun Yu; Ida Häggström; Zhiyong Zhou; Saikat Chatterjee; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; sparse signal processing; compressed sensing; Poisson denoising; positron emission tomography PET ; sinogram denoising; sinogram inpainting; deep learning; matematisk statistik; Mathematical Statistics;

    Sammanfattning : Much like a backwards computed Sudoku puzzle, starting from the completed number grid and working ones way down to a partially completed grid without damaging the route back to the full unique solution, this thesis tackles the challenges behind setting up a number puzzle in the context of biomedical imaging. By leveraging sparse signal processing theory, we study the means of practical undersampling of positron emission tomography (PET) measurements, an imaging modality in nuclear medicine that visualises functional processes within the body using radioactive tracers. LÄS MER

  7. 5. On Methods for Real Time Sampling and Distributions in Sampling

    Författare :Kadri Meister; Daniel Thorburn; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematical statistics; Finite population sampling; inferential issues; real time sampling; sequential sampling methods; negative sampling correlations; model-design-based inference; multivariate Bernoulli and multinomial designs; Matematisk statistik; Mathematical statistics; Matematisk statistik; Mathematical Statistics; matematisk statistik;

    Sammanfattning : This thesis is composed of six papers, all dealing with the issue of sampling from a finite population. We consider two different topics: real time sampling and distributions in sampling. The main focus is on Papers A–C, where a somewhat special sampling situation referred to as real time sampling is studied. LÄS MER