Improved Learning via k-DTW: A Novel Dissimilarity Measure for Curves

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Krivošija, Amer, Munteanu, Alexander, Nusser, André, Schwiegelshohn, Chris
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866910973759062016
author Krivošija, Amer
Munteanu, Alexander
Nusser, André
Schwiegelshohn, Chris
author_facet Krivošija, Amer
Munteanu, Alexander
Nusser, André
Schwiegelshohn, Chris
contents This paper introduces $k$-Dynamic Time Warping ($k$-DTW), a novel dissimilarity measure for polygonal curves. $k$-DTW has stronger metric properties than Dynamic Time Warping (DTW) and is more robust to outliers than the Fréchet distance, which are the two gold standards of dissimilarity measures for polygonal curves. We show interesting properties of $k$-DTW and give an exact algorithm as well as a $(1+\varepsilon)$-approximation algorithm for $k$-DTW by a parametric search for the $k$-th largest matched distance. We prove the first dimension-free learning bounds for curves and further learning theoretic results. $k$-DTW not only admits smaller sample size than DTW for the problem of learning the median of curves, where some factors depending on the curves' complexity $m$ are replaced by $k$, but we also show a surprising separation on the associated Rademacher and Gaussian complexities: $k$-DTW admits strictly smaller bounds than DTW, by a factor $\tildeΩ(\sqrt{m})$ when $k\ll m$. We complement our theoretical findings with an experimental illustration of the benefits of using $k$-DTW for clustering and nearest neighbor classification.
format Preprint
id arxiv_https___arxiv_org_abs_2505_23431
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Improved Learning via k-DTW: A Novel Dissimilarity Measure for Curves
Krivošija, Amer
Munteanu, Alexander
Nusser, André
Schwiegelshohn, Chris
Data Structures and Algorithms
Computational Geometry
Machine Learning
This paper introduces $k$-Dynamic Time Warping ($k$-DTW), a novel dissimilarity measure for polygonal curves. $k$-DTW has stronger metric properties than Dynamic Time Warping (DTW) and is more robust to outliers than the Fréchet distance, which are the two gold standards of dissimilarity measures for polygonal curves. We show interesting properties of $k$-DTW and give an exact algorithm as well as a $(1+\varepsilon)$-approximation algorithm for $k$-DTW by a parametric search for the $k$-th largest matched distance. We prove the first dimension-free learning bounds for curves and further learning theoretic results. $k$-DTW not only admits smaller sample size than DTW for the problem of learning the median of curves, where some factors depending on the curves' complexity $m$ are replaced by $k$, but we also show a surprising separation on the associated Rademacher and Gaussian complexities: $k$-DTW admits strictly smaller bounds than DTW, by a factor $\tildeΩ(\sqrt{m})$ when $k\ll m$. We complement our theoretical findings with an experimental illustration of the benefits of using $k$-DTW for clustering and nearest neighbor classification.
title Improved Learning via k-DTW: A Novel Dissimilarity Measure for Curves
topic Data Structures and Algorithms
Computational Geometry
Machine Learning
url https://arxiv.org/abs/2505.23431