{"id":{"repo_id":"duke","oai_identifier":"oai:dukespace.lib.duke.edu:10161/16373"},"canonical_url":"https://search.dev.ndltd.org/etd/duke/oai:dukespace.lib.duke.edu:10161/16373","repository":{"repo_id":"duke","name":"Duke University","base_url":"https://dukespace.lib.duke.edu/server/oai/request"},"display":{"title":"Non-Parametric Priors for Functional Data and Partition Labelling Models","abstract":"<p>Previous papers introduced a variety of extensions of the Dirichlet process to the func-</p><p>tional domain, focusing on the challenges presented by extending the stick-breaking</p><p>process. In this thesis some of these are examined in more detail for similarities</p><p>and differences in their stick-breaking extensions. Two broad classes of extensions</p><p>can be defined, differentiating by how the construction of functional mixture weights</p><p>are handled: one type of process views it as the product of a sequence of marginal</p><p>mixture weights, whereas the other specifies a joint mixture weight for an entire ob-</p><p>servation. These are termed “marginal” and “joint” labelling processes respectively,</p><p>and we show that there are significant differences in their posterior predictive perfor-</p><p>mance. Further investigation of the generalized functional Dirichlet process reveals</p><p>that a more fundamental difference exists. Whereas marginal labelling models nec-</p><p>essarily assign labels only at specific arguments, joint labelling models can allow for</p><p>the assignment of labels to random subsets of the domain of the function. This leads</p><p>naturally to the idea of a stochastic process based around a random partitioning of a</p><p>bounded domain, which we call the partitioned functional Dirichlet process. Here we</p><p>explicitly model the partitioning of the domain in a constrained manner, rather than</p><p>implicitly as happens in the generalized functional Dirichlet process. Comparisons</p><p>are made in terms of posterior predictive behaviour between this model, the general-</p><p>ized functional Dirichlet process and the functional Dirichlet process. We find that</p><p>the explicit modelling of the partitioning leads to more tractable computational and </p><p>more structured posterior predictive behaviour than in the generalized functional</p><p>Dirichlet process, while still offering increased flexibility over the functional Dirich-</p><p>let process. Finally, we extend the partitioned functional Dirichlet process to the</p><p>bivariate case.</p>","abstract_html":"&lt;p&gt;Previous papers introduced a variety of extensions of the Dirichlet process to the func-&lt;/p&gt;&lt;p&gt;tional domain, focusing on the challenges presented by extending the stick-breaking&lt;/p&gt;&lt;p&gt;process. In this thesis some of these are examined in more detail for similarities&lt;/p&gt;&lt;p&gt;and differences in their stick-breaking extensions. Two broad classes of extensions&lt;/p&gt;&lt;p&gt;can be defined, differentiating by how the construction of functional mixture weights&lt;/p&gt;&lt;p&gt;are handled: one type of process views it as the product of a sequence of marginal&lt;/p&gt;&lt;p&gt;mixture weights, whereas the other specifies a joint mixture weight for an entire ob-&lt;/p&gt;&lt;p&gt;servation. These are termed “marginal” and “joint” labelling processes respectively,&lt;/p&gt;&lt;p&gt;and we show that there are significant differences in their posterior predictive perfor-&lt;/p&gt;&lt;p&gt;mance. Further investigation of the generalized functional Dirichlet process reveals&lt;/p&gt;&lt;p&gt;that a more fundamental difference exists. Whereas marginal labelling models nec-&lt;/p&gt;&lt;p&gt;essarily assign labels only at specific arguments, joint labelling models can allow for&lt;/p&gt;&lt;p&gt;the assignment of labels to random subsets of the domain of the function. This leads&lt;/p&gt;&lt;p&gt;naturally to the idea of a stochastic process based around a random partitioning of a&lt;/p&gt;&lt;p&gt;bounded domain, which we call the partitioned functional Dirichlet process. Here we&lt;/p&gt;&lt;p&gt;explicitly model the partitioning of the domain in a constrained manner, rather than&lt;/p&gt;&lt;p&gt;implicitly as happens in the generalized functional Dirichlet process. Comparisons&lt;/p&gt;&lt;p&gt;are made in terms of posterior predictive behaviour between this model, the general-&lt;/p&gt;&lt;p&gt;ized functional Dirichlet process and the functional Dirichlet process. We find that&lt;/p&gt;&lt;p&gt;the explicit modelling of the partitioning leads to more tractable computational and &lt;/p&gt;&lt;p&gt;more structured posterior predictive behaviour than in the generalized functional&lt;/p&gt;&lt;p&gt;Dirichlet process, while still offering increased flexibility over the functional Dirich-&lt;/p&gt;&lt;p&gt;let process. Finally, we extend the partitioned functional Dirichlet process to the&lt;/p&gt;&lt;p&gt;bivariate case.&lt;/p&gt;","abstract_has_math":false,"creators":["Hellmayr, Christoph Stefan"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Gelfand, Alan E"],"committee_chairs":[],"committee_members":[],"year":2017,"date_issued":"2017","date_published":"2017","updated_at":"2026-07-24T02:06:56Z","subjects":["Statistics","Bayesian","Functional Data","Non-Parametrics"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/10161/16373","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Gelfand, Alan E"]},{"key":"dc:creator","label":"Author","values":["Hellmayr, Christoph Stefan"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2018-03-20T17:56:56Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2018-03-20T17:56:56Z"]},{"key":"dc:date.issued","label":"Date","values":["2017"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Statistics","Bayesian","Functional Data","Non-Parametrics"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/10161/16373"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["<p>Previous papers introduced a variety of extensions of the Dirichlet process to the func-</p><p>tional domain, focusing on the challenges presented by extending the stick-breaking</p><p>process. In this thesis some of these are examined in more detail for similarities</p><p>and differences in their stick-breaking extensions. Two broad classes of extensions</p><p>can be defined, differentiating by how the construction of functional mixture weights</p><p>are handled: one type of process views it as the product of a sequence of marginal</p><p>mixture weights, whereas the other specifies a joint mixture weight for an entire ob-</p><p>servation. These are termed “marginal” and “joint” labelling processes respectively,</p><p>and we show that there are significant differences in their posterior predictive perfor-</p><p>mance. Further investigation of the generalized functional Dirichlet process reveals</p><p>that a more fundamental difference exists. Whereas marginal labelling models nec-</p><p>essarily assign labels only at specific arguments, joint labelling models can allow for</p><p>the assignment of labels to random subsets of the domain of the function. This leads</p><p>naturally to the idea of a stochastic process based around a random partitioning of a</p><p>bounded domain, which we call the partitioned functional Dirichlet process. Here we</p><p>explicitly model the partitioning of the domain in a constrained manner, rather than</p><p>implicitly as happens in the generalized functional Dirichlet process. Comparisons</p><p>are made in terms of posterior predictive behaviour between this model, the general-</p><p>ized functional Dirichlet process and the functional Dirichlet process. We find that</p><p>the explicit modelling of the partitioning leads to more tractable computational and </p><p>more structured posterior predictive behaviour than in the generalized functional</p><p>Dirichlet process, while still offering increased flexibility over the functional Dirich-</p><p>let process. Finally, we extend the partitioned functional Dirichlet process to the</p><p>bivariate case.</p>"]},{"key":"dc:title","label":"Title","values":["Non-Parametric Priors for Functional Data and Partition Labelling Models"]}]}],"canonical_facts":{"dc:contributor.advisor":["Gelfand, Alan E"],"dc:creator":["Hellmayr, Christoph Stefan"],"dc:date.accessioned":["2018-03-20T17:56:56Z"],"dc:date.available":["2018-03-20T17:56:56Z"],"dc:date.issued":["2017"],"dc:description.abstract":["<p>Previous papers introduced a variety of extensions of the Dirichlet process to the func-</p><p>tional domain, focusing on the challenges presented by extending the stick-breaking</p><p>process. In this thesis some of these are examined in more detail for similarities</p><p>and differences in their stick-breaking extensions. Two broad classes of extensions</p><p>can be defined, differentiating by how the construction of functional mixture weights</p><p>are handled: one type of process views it as the product of a sequence of marginal</p><p>mixture weights, whereas the other specifies a joint mixture weight for an entire ob-</p><p>servation. These are termed “marginal” and “joint” labelling processes respectively,</p><p>and we show that there are significant differences in their posterior predictive perfor-</p><p>mance. Further investigation of the generalized functional Dirichlet process reveals</p><p>that a more fundamental difference exists. Whereas marginal labelling models nec-</p><p>essarily assign labels only at specific arguments, joint labelling models can allow for</p><p>the assignment of labels to random subsets of the domain of the function. This leads</p><p>naturally to the idea of a stochastic process based around a random partitioning of a</p><p>bounded domain, which we call the partitioned functional Dirichlet process. Here we</p><p>explicitly model the partitioning of the domain in a constrained manner, rather than</p><p>implicitly as happens in the generalized functional Dirichlet process. Comparisons</p><p>are made in terms of posterior predictive behaviour between this model, the general-</p><p>ized functional Dirichlet process and the functional Dirichlet process. We find that</p><p>the explicit modelling of the partitioning leads to more tractable computational and </p><p>more structured posterior predictive behaviour than in the generalized functional</p><p>Dirichlet process, while still offering increased flexibility over the functional Dirich-</p><p>let process. Finally, we extend the partitioned functional Dirichlet process to the</p><p>bivariate case.</p>"],"dc:identifier.uri":["https://hdl.handle.net/10161/16373"],"dc:subject":["Statistics","Bayesian","Functional Data","Non-Parametrics"],"dc:title":["Non-Parametric Priors for Functional Data and Partition Labelling Models"],"dc:type":["Dissertation"]},"updated_at":"2026-07-24T02:06:56Z"}