# Geometry and Statistics in Data Sciences, Paris

September 5, 2022 to December 9, 2022
IHP
Europe/Paris timezone
Financial support for the participation to the quarter is now closed

## Marina Meila - Manifold Learning, Explanations and Eigenflows

Oct 4, 2022, 2:30 PM
1h
Amphitheater Hermite, IHP

### Description

This talk will extend Manifold Learning in two directions.
First, we ask if it is possible, in the case of scientific data where quantitative prior knowledge is abundant, to explain a data manifold by new coordinates, chosen from a set of scientifically meaningful functions?
Second, we ask how popular Manifold Learning tools and their applications can be recreated in the space of vector fields and flows on a manifold.
Central to this approach is the order 1-Laplacian of a manifold, $\Delta_1$, whose eigen-decomposition into gradient, harmonic, and curl, known as the Helmholtz-Hodge Decomposition, provides a basis for all vector fields on a manifold. We present an estimator for $\Delta_1$, and based on it we develop a variety of applications. Among them, visualization of the principal harmonic, gradient or curl flows on a manifold, smoothing and semi-supervised learning of vector fields, 1-Laplacian regularization. In topological data analysis, we describe the 1st-order analogue of spectral clustering, which amounts to prime manifold decomposition. Furthermore, from this decomposition a new algorithm for finding shortest independent loops follows. The algorithms are illustrated on a variety of real data sets.
Joint work with Yu-Chia Chen, Samson Koelle, Hanyu Zhang and Ioannis Kevrekidis

### Presentation materials

There are no materials yet.