Sökning: "unequal probabilities"

Hittade 5 avhandlingar innehållade orden unequal probabilities.

  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. On Clustering of Random Points in the Plane and in Space

    Författare :Marianne Månsson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; geometric probability; integral geometry; convex sets; random intersections; mixed volumes; scan statistics; Poisson approximation; Stein-Chen method; convergence of point processes; scan statistics;

    Sammanfattning : If n points are independently and uniformly distributed in a large rectangular parallelepiped, A in Rd, d =2,3, they may possibly aggregate in such a way that they are contained in some translate of a given convex set C in A. If the points are replaced by copies of C, these translated sets may have a non-empty intersection. LÄS MER

  7. 5. Statistical modeling in international large-scale assessments

    Författare :Inga Laukaityte; Marie Wiberg; Kenny Bränberg; Ewa Rolfsman; Bernard Veldkamp; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; multilevel model; plausible values; sampling weights; missing information; multiple imputation; non-monotone missing pattern; TIMSS; PISA; Statistics; statistik; pedagogik; Education;

    Sammanfattning : This thesis contributes to the area of research based on large-scale educational assessments, focusing on the application of multilevel models. The role of sampling weights, plausible values (response variable imputed multiple times) and imputation methods are demonstrated by simulations and applications to TIMSS (Trends in International Mathematics and Science Study) and PISA (Programme for International Student Assessment) data. LÄS MER