HKUEMS :: Event Details

50th Anniv. Seminar Series on 'Principal component analysis for functional...' by Mr. Xiongtao DAI
posted by Department of Statistics and Actuarial Science for HKU and Public
Event Type: Public Lecture/Forum/Seminar/Workshop/Conference/Symposium
Event Nature: Science & Technology

Event Details

DEPARTMENT OF STATISTICS AND ACTUARIAL SCIENCE
THE UNIVERSITY OF HONG KONG

50th Anniversary Seminar Series

Mr. Xiongtao DAI
University of California, Davis
USA

will give a talk

entitled

PRINCIPAL COMPONENT ANALYSIS FOR FUNCTIONAL DATA ON RIEMANNIAN MANIFOLDS AND SPHERES

Abstract

Functional data analysis on nonlinear manifolds has drawn recent interest. Sphere-valued functional data, which are encountered for example as movement trajectories on the surface of the earth, are an important special case. In this talk, we consider a principal component analysis for smooth Riemannian manifold-valued functional data, which respects the intrinsic geometry of the manifold. Riemannian functional principal component analysis (RFPCA) is carried out by first mapping the manifold-valued data through Riemannian logarithm maps to linear tangent spaces around the time-varying Frechet mean function, and then performing a classical multivariate functional principal component analysis. Representations of the sample functions and the eigenfunctions on the original manifold are then obtained with exponential maps. We derive a central limit theorem for the mean function, as well as root-n uniform convergence rates for other model components. Our applications include a novel framework for the analysis of longitudinal compositional data, achieved by mapping longitudinal compositional data to trajectories on the sphere, illustrated with longitudinal fruit fly behavior patterns. Riemannian functional principal component analysis is shown to be superior in terms of trajectory recovery and predictive power in comparison to an unrestricted method.

Date/Time23/01/2018 10:30-11:30
VenueRoom 301, Run Run Shaw Building, HKU
LanguageEnglish
Programmeclick to view
10:15 to 10:30 Refreshments will be served outside Room 301 Run Run Shaw Building
10:30 to 11:30 Seminar

Registration Instruction

Registration is not required.

Contact Information

For further information, please visit:
http://www.saasweb.hku.hk/seminar/seminar.php

Should you have any enquiries, please feel free to contact Ms. Irene Cheung by email at saas@hku.hk or by phone at 3917 2466 or by fax at 2858 9041.