Sökning: "penalized likelihood"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden penalized likelihood.

  1. 1. Essays on Estimation Methods for Factor Models and Structural Equation Models

    Författare :Shaobo Jin; Fan Yang-Wallentin; Rolf Larsson; Li Cai; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; shrinkage; factor rotation; penalized maximum likelihood; pseudo-maximum likelihood; multi-group analysis; ordinal data; robustness; Statistics; Statistik;

    Sammanfattning : This thesis which consists of four papers is concerned with estimation methods in factor analysis and structural equation models. New estimation methods are proposed and investigated.In paper I an approximation of the penalized maximum likelihood (ML) is introduced to fit an exploratory factor analysis model. LÄS MER

  3. 2. Dating Divergence Times in Phylogenies

    Författare :Cajsa Lisa Anderson; Kåre Bremer; Katleen M. Pryer; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; systematic biology; divergence time; nonprametric rate smoothing; Bayesian; multidivtime; eudicots; Neoaves; monocots; dating; molecular clock; relaxed clock; age constraint; fossil; calibration; PATHd8; penalized likelihood; Biology; Biologi;

    Sammanfattning : This thesis concerns different aspects of dating divergence times in phylogenetic trees, using molecular data and multiple fossil age constraints.Datings of phylogenetically basal eudicots, monocots and modern birds (Neoaves) are presented. Large phylograms and multiple fossil constraints were used in all these studies. LÄS MER

  4. 3. Latent variable models for multivariate survival and count data

    Författare :Samuli Ripatti; David Clayton; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; matematisk statistik; Mathematical Statistics;

    Sammanfattning : This thesis consists of three papers on multivariate frailty models and one paper on the use of latent class models in genetic association studies. The common theme through the four papers is the use of latent variables to capture complex dependence structures in the data. LÄS MER

  5. 4. Between open systems and closed doors : the needs and perceptions of parents of children with cognitive disabilities in educational settings

    Författare :Lise Roll-Pettersson; Rune Simeonsson; Stockholms universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; ABCX model; Cognitive disability; Parents; Teachers; Föräldrar till barn med funktionsnedsättning; Elever med särskilda behov; Lärarrollen; Sverige; pedagogik; Education;

    Sammanfattning : This thesis consists of three papers on multivariate frailty models and one paper on the use of latent class models in genetic association studies. The common theme through the four papers is the use of latent variables to capture complex dependence structures in the data. LÄS MER

  7. 5. Comparative network analysis of human cancer: sparse graphical models with modular constraints and sample size correction

    Författare :José Sánchez; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Inverse covariance matrix; precision matrix; graphical models; high-dimension; low-sample; networks; sparsity; fused lasso; elastic net; cancer.; fused lasso;

    Sammanfattning : In the study of transcriptional data for different groups (e.g. cancer types) it's reasonable to assume that some dependencies between genes on a transcriptional or genetic variants level are common across groups. Also, that this property is preserved locally, thus defining a modular structure in the model networks. LÄS MER