Sökning: "Bayesian clustering"

Visar resultat 6 - 10 av 20 avhandlingar innehållade orden Bayesian clustering.

1. 6. Some Contributions to Heteroscedastic Time Series Analysis and Computational Aspects of Bayesian VARs

   Författare :Oskar Gustafsson; Pär Stockhammar; Domenico Giannone; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Time series; heteroscedasticity; variance stabilizing filters; Bayesian vector autoregressions; Bayesian optimization; variational inference; Statistics; statistik;

   Sammanfattning : Time-dependent volatility clustering (or heteroscedasticity) in macroeconomic and financial time series has been analyzed for more than half a century. The inefficiencies it causes in various inference procedures are well known and understood. Despite this, heteroscedasticity is surprisingly often neglected in practical work. LÄS MER

3. 7. From genomes to post-processing of Bayesian inference of phylogeny

   Författare :Raja Hashim Ali; Lars Arvestad; Dannie Durand; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bayesian inference; Computer Science; Datalogi;

   Sammanfattning : Life is extremely complex and amazingly diverse; it has taken billions of years of evolution to attain the level of complexity we observe in nature now and ranges from single-celled prokaryotes to multi-cellular human beings. With availability of molecular sequence data, algorithms inferring homology and gene families have emerged and similarity in gene content between two genes has been the major signal utilized for homology inference. LÄS MER

4. 8. Computational Problems in Modeling Evolution and Inferring Gene Families

   Författare :Mehmood Alam Khan; Lars Arvestad; Jens Lagergren; Christophe Dessimoz; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Evolution; Phylogenetics; Lateral Gene Transfer; Gene Families; Clustering; Datalogi; Computer Science;

   Sammanfattning : Over the last few decades, phylogenetics has emerged as a very promising field, facilitating a comparative framework to explain the genetic relationships among all the living organisms on earth. These genetic relationships are typically represented by a bifurcating phylogenetic tree — the tree of life. LÄS MER

5. 9. Reticulate Evolution in Diphasiastrum (Lycopodiaceae)

   Författare :Sunniva Margrethe Due Aagaard; Niklas Wikström; Tom A. Ranker; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; admixture analysis; Bayesian clustering; Diphasiastrum; Feulgen DNA image densitometry; homoploid hybridization; Lycopodiaceae; phylogenetic analysis; polyploidy; reticulate evolution; Systematics and phylogenetics; Systematik och fylogeni; systematisk botanik; Systematic Botany;

   Sammanfattning : In this thesis relationships and the occurrence of reticulate evolutionary events in the club moss genus Diphasiastrum are investigated. Diphasiastrum is initially established as a monophyletic group within Lycopodiaceae using non recombinant chloroplast sequence data. LÄS MER

7. 10. On Data Mining and Classification Using a Bayesian Confidence Propagation Neural Network

   Författare :Roland Orre; KTH; []
   Nyckelord :data mining; bcpnn; classification; neural network;

   Sammanfattning : The aim of this thesis is to describe how a statisticallybased neural network technology, here named BCPNN (BayesianConfidence Propagation Neural Network), which may be identifiedby rewriting Bayes' rule, can be used within a fewapplications, data mining and classification with credibilityintervals as well as unsupervised pattern recognition.BCPNN is a neural network model somewhat reminding aboutBayesian decision trees which are often used within artificialintelligence systems. LÄS MER