The geometry of Stein's method of moments: A canonical decomposition via score matching

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Nagai, Mitsuki, Yano, Keisuke
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911512183963648
author Nagai, Mitsuki
Yano, Keisuke
author_facet Nagai, Mitsuki
Yano, Keisuke
contents In this paper, we elucidate the geometry of Stein's method of moments (SMoM). SMoM is a parameter estimation method based on the Stein operator, and yields a wide class of estimators that do not depend on the normalizing constant. We present a canonical decomposition of an SMoM estimator after centering the score matching estimator, which sheds light on the central role of the score matching within the SMoM framework. Using this decomposition, we construct an SMoM estimator that improves upon the score matching estimator in the asymptotic variance. We also discuss the connection between SMoM and the Wasserstein geometry. Specifically, using the Wasserstein score function, we provide a geometrical interpretation of the gap in the asymptotic variance between the score matching estimator and the maximum likelihood estimator. Furthermore, it is shown that the score matching estimator is asymptotically efficient if and only if the Fisher score functions span the same space as the Wasserstein score functions.
format Preprint
id arxiv_https___arxiv_org_abs_2603_12843
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle The geometry of Stein's method of moments: A canonical decomposition via score matching
Nagai, Mitsuki
Yano, Keisuke
Statistics Theory
Methodology
In this paper, we elucidate the geometry of Stein's method of moments (SMoM). SMoM is a parameter estimation method based on the Stein operator, and yields a wide class of estimators that do not depend on the normalizing constant. We present a canonical decomposition of an SMoM estimator after centering the score matching estimator, which sheds light on the central role of the score matching within the SMoM framework. Using this decomposition, we construct an SMoM estimator that improves upon the score matching estimator in the asymptotic variance. We also discuss the connection between SMoM and the Wasserstein geometry. Specifically, using the Wasserstein score function, we provide a geometrical interpretation of the gap in the asymptotic variance between the score matching estimator and the maximum likelihood estimator. Furthermore, it is shown that the score matching estimator is asymptotically efficient if and only if the Fisher score functions span the same space as the Wasserstein score functions.
title The geometry of Stein's method of moments: A canonical decomposition via score matching
topic Statistics Theory
Methodology
url https://arxiv.org/abs/2603.12843