Sökning: "clustered"

Visar resultat 1 - 5 av 177 avhandlingar innehållade ordet clustered.

  1. 1. Semiparametric survival models for routine register data

    Författare :Frank Eriksson; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Survival; transformation; clustered; likelihood; random effects; case-cohort; routine register; semiparametric; clustered;

    Sammanfattning : Routine registers offer researchers opportunities to carry out studies of covariate effects on lifetimes of rare diseases otherwise infeasible because of the large cohorts required. Familial relationships necessary for analysis of environmental or genetic factors can be identified by record linking. LÄS MER

  2. 2. Generalised linear models with clustered data

    Författare :Henrik Holmberg; Göran Broström; Kenneth Carling; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Statistics; Statistik; Statistics; statistik;

    Sammanfattning : In situations where a large data set is partitioned into many relativelysmall clusters, and where the members within a cluster have some common unmeasured characteristics, the number of parameters requiring estimation tends to increase with sample size if a fixed effects model is applied. This fact causes the assumptions underlying asymptotic results to be violated. LÄS MER

  3. 3. Generalized linear models with clustered data

    Författare :Henrik Holmberg; Erling Häggström Lundevaller; Göran Broström; Douglas Bates; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Statistics; statistik;

    Sammanfattning : In situations where a large data set is partitioned into many relatively small groups, and where the members within a group have some common unmeasured characteristics, the number of parameters requiring estimation tends to increase with sample size if a fixed effects model is applied. This fact causes the assumptions underlying asymptotic results to be violated. LÄS MER

  4. 4. Induction and repair of clustered DNA damage sites after exposure to ionizing radiation

    Författare :Andris Abramenkovs; Bo Stenerlöw; Peter O'Neill; Uppsala universitet; []
    Nyckelord :NHEJ; DSB repair; clustered DNA damage; DNA repair; DNA-PKcs; HSCS; Ra-223; ionizing radiation; Medicinsk vetenskap; Medical Science;

    Sammanfattning : The mechanisms that maintain genomic stability safeguard cells from constant DNA damage produced by endogenous and external stressors. Therefore, this thesis aimed to specifically address questions regarding the requirement and involvement of DNA repair proteins in the repair of various types of radiation-induced DNA damage. LÄS MER

  5. 5. Correlated random effects models for clustered survival data

    Författare :Frank Eriksson; Chalmers tekniska högskola; Göteborgs universitet; Gothenburg University; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; competing risks; case-cohort; semiparametric; Survival analysis; random effects; routine register; frailty model; Survival analysis; frailty model; competing risks; random effects; case-cohort; routine register; semiparametric;

    Sammanfattning : Frailty models are frequently used to analyse clustered survival data in medical contexts. The frailties, or random effects, are used to model the association between individual survival times within clusters. LÄS MER