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Visar resultat 1 - 5 av 11 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. 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

  3. 2. Sequential Monte Carlo methods for conjugate state-space models

    Författare :Anna Wigren; Fredrik Lindsten; Lawrence Murray; Riccardo Sven Risuleo; Simon Maskell; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sequential Monte Carlo; Particle filter; Markov chain Monte Carlo; Conjugacy; State-space model; Probabilistic programming; Electrical Engineering with specialization in Signal Processing; Elektroteknik med inriktning mot signalbehandling;

    Sammanfattning : Bayesian inference in state-space models requires the solution of high-dimensional integrals, which is intractable in general. A viable alternative is to use sample-based methods, like sequential Monte Carlo, but this introduces variance into the inferred quantities that can sometimes render the estimates useless. LÄS MER

  4. 3. A Bayesian approach to retrospective detection of change-points in road surface measurements

    Författare :Fridtjof Thomas; Urban Hjort; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Change-point detection; retrospective view; autoregressive processes; minimal imaginary training sample; road surface measurements; international roughness index; rutting; Laser-RST vehicles; road maintenance; pavement management; statistik; Statistics;

    Sammanfattning : First-order autoregressive processes are analysed for sudden changes in parameter value. In its most general form, a multivariate vector of measurements is allowed, and no prior knowledge about the involved parameters is required. LÄS MER

  5. 4. Particle filters and Markov chains for learning of dynamical systems

    Författare :Fredrik Lindsten; Thomas B. Schön; Lennart Ljung; Fredrik Gustafsson; Arnaud Doucet; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Bayesian learning; System identification; Sequential Monte Carlo; Markov chain Monte Carlo; Particle MCMC; Particle filters; Particle smoothers;

    Sammanfattning : Sequential Monte Carlo (SMC) and Markov chain Monte Carlo (MCMC) methods provide computational tools for systematic inference and learning in complex dynamical systems, such as nonlinear and non-Gaussian state-space models. This thesis builds upon several methodological advances within these classes of Monte Carlo methods. LÄS MER

  7. 5. Towards a Model of General Text Complexity for Swedish

    Författare :Johan Falkenjack; Arne Jönsson; Robert Östling; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; HUMANIORA; HUMANITIES;

    Sammanfattning : In an increasingly networked world, where the amount of written information is growing at a rate never before seen, the ability to read and absorb written information is of utmost importance for anything but a superficial understanding of life's complexities. That is an example of a sentence which is not very easy to read. LÄS MER