Sökning: "Statistik"

Visar resultat 21 - 25 av 1307 avhandlingar innehållade ordet Statistik.

  1. 21. Multiple Time Scales and Longitudinal Measurements in Event History Analysis

    Författare :Danardono; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Statistics; Cox regression; multiple events; proportiona hazards; random effects; survival analysis; time-dependent covariates; time origin; Statistik; Statistics; Statistik; Statistics; statistik;

    Sammanfattning : A general time-to-event data analysis known as event history analysis is considered. The focus is on the analysis of time-to-event data using Cox's regression model when the time to the event may be measured from different origins giving several observable time scales and when longitudinal measurements are involved. LÄS MER

  3. 22. Optimal Design of Experiments for the Quadratic Logistic Model

    Författare :Ellinor Fackle Fornius; Hans Nyquist; Christos Kitsos; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Logistic regression; D-optimality; c-optimality; Canonical design space; Maximum likelihood estimation; Sequential design; Stochastic approximation; Statistics; Statistik; statistik; Statistics;

    Sammanfattning : Optimal design of experiments for binary data is the topic of this thesis. A particular logistic model including a quadratic term in the linear predictor is considered. Determining an optimal design for this model is complicated by the fact that the optimal design is dependent on the unknown true parameters. LÄS MER

  4. 23. Essays on spatial point processes and bioinformatics

    Författare :Jessica Fahlén; Patrik Rydén; Xavier de Luna; Yudi Pawitan; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Coverage process; vacancy; microarray; pre-processing; sensitivity; bias; dye-normalization; FFPE; storage time effects; Statistics; Statistik; Statistics; statistik;

    Sammanfattning : This thesis consists of two separate parts. The first part consists of one paper and considers problems concerning spatial point processes and the second part includes three papers in the field of bioinformatics. LÄS MER

  5. 24. 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. 25. Essays on Model Assisted Survey Planning

    Författare :Anders Holmberg; Bengt Rosén; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Statistics; Statistik; Statistics; Statistik; Statistics; statistik;

    Sammanfattning : The quality of sample survey results is to a large degree dependent on decisions made by survey statisticians at the planning stage. The first paper studies two issues related to the planning stage: (i) the sensitivity of model assumptions concerning the relation between the size measure and a study variable in without replacement probability proportional-to-size sampling (πps sampling), and (ii) properties of practicable sample selection schemes for fixed size πps sampling. LÄS MER