Efficient Parallel Transport of Deformations in Time Series of Images: From Schild's to Pole Ladder
Group-wise analysis of time series of images requires to compare longitudinal evolutions of images observed on different subjects. In medical imaging, longitudinal anatomical changes can be modeled thanks to non-rigid registration of follow-up images. ...
Multivariate Tensor-Based Morphometry with a Right-Invariant Riemannian Distance on GL+(n)
Tensor-based morphometry (TBM) studies encode the anatomical information in spatial deformations which are locally characterized by Jacobian matrices. Current methods perform voxel-wise statistical analysis on some features, such as the Jacobian ...
Intrinsic Polynomials for Regression on Riemannian Manifolds
We develop a framework for polynomial regression on Riemannian manifolds. Unlike recently developed spline models on Riemannian manifolds, Riemannian polynomials offer the ability to model parametric polynomials of all integer orders, odd and even. An ...
Density Estimators of Gaussian Type on Closed Riemannian Manifolds
We prove consistency results for two types of density estimators on a closed, connected Riemannian manifold under suitable regularity conditions. The convergence rates are consistent with those in Euclidean space as well as those obtained for a ...
Overview of the Geometries of Shape Spaces and Diffeomorphism Groups
This article provides an overview of various notions of shape spaces, including the space of parametrized and unparametrized curves, the space of immersions, the diffeomorphism group and the space of Riemannian metrics. We discuss the Riemannian metrics ...
On Means and Their Asymptotics: Circles and Shape Spaces
We survey some effects that singular strata may have in the positive curvature context of circles and shape spaces when conducting (semi-)intrinsic statistical analyses. Here, the analysis of data on a stratified space is based on statistical ...
Backwards Principal Component Analysis and Principal Nested Relations
In non-Euclidean data spaces represented by manifolds (or more generally stratified spaces), analogs of principal component analysis can be more easily developed using a backwards approach. There has been a gradual evolution in the application of this ...
Diffusion on Some Simple Stratified Spaces
A variety of different imaging techniques produce data which naturally lie in stratified spaces. These spaces consist of smooth regions of maximal dimension glued together along lower dimensional boundaries. Diffusion processes are important as they can ...
Tree-Oriented Analysis of Brain Artery Structure
- Sean Skwerer,
- Elizabeth Bullitt,
- Stephan Huckemann,
- Ezra Miller,
- Ipek Oguz,
- Megan Owen,
- Vic Patrangenaru,
- Scott Provan,
- J. S. Marron
Statistical analysis of magnetic resonance angiography (MRA) brain artery trees is performed using two methods for mapping brain artery trees to points in phylogenetic treespace: cortical landmark correspondence and descendant correspondence. The ...
Equi-affine Invariant Geometry for Shape Analysis
Traditional models of bendable surfaces are based on the exact or approximate invariance to deformations that do not tear or stretch the shape, leaving intact an intrinsic geometry associated with it. These geometries are typically defined using either ...
Stable Length Estimates of Tube-Like Shapes
Motivated by applications in biology, we present an algorithm for estimating the length of tube-like shapes in 3-dimensional Euclidean space. In a first step, we combine the tube formula of Weyl with integral geometric methods to obtain an integral ...