Sökning: "sample selection bias"

Visar resultat 1 - 5 av 41 avhandlingar innehållade orden sample selection bias.

  1. 1. Genome Variation in Human Populations : Exploring the Effects of Demographic History and the Potential for Mapping of Complex Traits

    Författare :Åsa Johansson; Ulf Gyllensten; Marta Alarcon; Andrew Clark; Uppsala universitet; []
    Nyckelord :Genetics; genetics; evolution; microsatellie; SNP; selection; linkage disequilibrium; haplotype; Genetik;

    Sammanfattning : A major challenge in human genetics is to understand the genetic variation underlying common diseases. In this thesis, I focus on forces creating differences between individuals and genomic regions, methods for characterizing genomic variation, and the association between genomic and phenotypic variation. LÄS MER

  3. 2. Continuous-Time Models in Kernel Smoothing

    Författare :Martin Sköld; Matematisk statistik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; deconvolution; errors-in-variables; continuous time; dependent data; bandwidth selection; asymptotic variance; Density estimation; kernel smoothing; size bias.; Mathematics; Matematik;

    Sammanfattning : This thesis consists of five papers (Papers A-E) treating problems in non-parametric statistics, especially methods of kernel smoothing applied to density estimation for stochastic processes (Papers A-D) and regression analysis (Paper E). A recurrent theme is to, instead of treating highly positively correlated data as ``asymptotically independent'', take advantage of local dependence structures by using continuous-time models. LÄS MER

  4. 3. Gotta survey somebody : Methodological challenges in population studies of older people

    Författare :Susanne Kelfve; Carin Lennartsson; Mats Thorslund; Mark D Hayward; Stockholms universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Population studies; Older people; Representativeness; Survey design; Non-response; Sample selection; Selective attrition; Social inequality; Health outcomes; Sociology; sociologi;

    Sammanfattning : Conducting representative surveys of older people is challenging. This thesis aims to analyze a) the characteristics of individuals at risk of being underrepresented in surveys of older people, b) the systematic errors likely to occur as a result of these selections, and c) whether these systematic errors can be minimized by weighting adjustments. LÄS MER

  5. 4. Deep learning based simulation for automotive software development

    Författare :Dhasarathy Parthasarathy; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; automotive software testing; latent space arithmetic; generative adversarial networks; explainable AI; sample selection bias;

    Sammanfattning : The automotive industry is in the midst of a new reality where software is increasingly becoming the primary tool for delivering value to customers. While this has vastly improved their product offerings, vehicle manufacturers are increasingly facing the need to continuously develop, test, and deliver functionality, while maintaining high levels of quality. LÄS MER

  7. 5. Estimating Interviewer Effects in Sample Surveys : Some Contributions

    Författare :Peter Lundquist; Stig Danielsson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Response variance; survey nonsampling error; interviewer effects; interpenetration; power; Statistics; Statistik;

    Sammanfattning : This thesis focuses on measurement errors that could be ascribed to the interviewers. To study interviewer variability a measurement error model is formulated which makes a clear distinction between three sources of randomness: the sample selection, interviewer assignment, and interviewing. LÄS MER