Repository logo
 

Mean variants on matrix manifolds

dc.contributor.authorMarks, Justin D., author
dc.contributor.authorPeterson, Chris, advisor
dc.contributor.authorKirby, Michael, advisor
dc.contributor.authorBates, Dan, committee member
dc.contributor.authorAnderson, Chuck, committee member
dc.date.accessioned2007-01-03T08:26:22Z
dc.date.available2007-01-03T08:26:22Z
dc.date.issued2012
dc.description.abstractThe geometrically elegant Stiefel and Grassmann manifolds have become organizational tools for data applications, such as illumination spaces for faces in digital photography. Modern data analysis involves increasingly large-scale data sets, both in terms of number of samples and number of features per sample. In circumstances such as when large-scale data has been mapped to a Stiefel or Grassmann manifold, the computation of mean representatives for clusters of points on these manifolds is a valuable tool. We derive three algorithms for determining mean representatives for a cluster of points on the Stiefel manifold and the Grassmann manifold. Two algorithms, the normal mean and the projection mean, follow the theme of the Karcher mean, relying upon inversely related maps that operate between the manifold and the tangent bundle. These maps are informed by the geometric definition of the tangent bundle and the normal bundle. From the cluster of points, each algorithm exploits these maps in a predictor/corrector loop until converging, with prescribed tolerance, to a fixed point. The fixed point acts as the normal mean representative, or projection mean representative, respectively, of the cluster. This method shares its principal structural characteristics with the Karcher mean, but utilizes a distinct pair of inversely related maps. The third algorithm, called the flag mean, operates in a context comparable to a generalized Grassmannian. It produces a mean subspace of arbitrary dimension. We provide applications and discuss generalizations of these means to other manifolds.
dc.format.mediumborn digital
dc.format.mediumdoctoral dissertations
dc.identifierMarks_colostate_0053A_11461.pdf
dc.identifierETDF2012500311MATH
dc.identifier.urihttp://hdl.handle.net/10217/71570
dc.languageEnglish
dc.language.isoeng
dc.publisherColorado State University. Libraries
dc.relation.ispartof2000-2019
dc.rightsCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.
dc.subjectGrassmann
dc.subjectmanifold
dc.subjectmean
dc.subjectStiefel
dc.subjectsubspace
dc.titleMean variants on matrix manifolds
dc.typeText
dcterms.rights.dplaThis Item is protected by copyright and/or related rights (https://rightsstatements.org/vocab/InC/1.0/). You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
thesis.degree.disciplineMathematics
thesis.degree.grantorColorado State University
thesis.degree.levelDoctoral
thesis.degree.nameDoctor of Philosophy (Ph.D.)

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
Marks_colostate_0053A_11461.pdf
Size:
1.33 MB
Format:
Adobe Portable Document Format
Description: