Structured Sampling for Robust Euclidean Distance Geometry
Chandra Kundu, Abiy Tasissa, HanQin Cai
TL;DR
This work tackles robust Euclidean distance geometry in a setting with anchor and target nodes where anchor–anchor distances are exact but anchor–target distances suffer sparse outliers. It introduces Structured Robust EDG, a localized pipeline that first denoises the corrupted anchor–target block $F$ with Robust PCA and then uses Nyström completion to recover the full Gram matrix $X$ from the available blocks, avoiding the missing $G$ block. The recovered Gram matrix is projected onto a rank-$r$ positive semidefinite space to yield coordinates up to rigid motion, enabling accurate point reconstruction with relatively few anchors. Experiments on synthetic sensor localization data and real protein structures demonstrate robust recovery under high corruption and scalability to large molecules, highlighting practical impact in localization and molecular structure analysis.
Abstract
This paper addresses the problem of estimating the positions of points from distance measurements corrupted by sparse outliers. Specifically, we consider a setting with two types of nodes: anchor nodes, for which exact distances to each other are known, and target nodes, for which complete but corrupted distance measurements to the anchors are available. To tackle this problem, we propose a novel algorithm powered by Nyström method and robust principal component analysis. Our method is computationally efficient as it processes only a localized subset of the distance matrix and does not require distance measurements between target nodes. Empirical evaluations on synthetic datasets, designed to mimic sensor localization, and on molecular experiments, demonstrate that our algorithm achieves accurate recovery with a modest number of anchors, even in the presence of high levels of sparse outliers.
