Hypothesis testing on invariant subspaces of non-diagonalizable matrices with applications to network statistics

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Simons, Jérôme R.
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909834308222976
author Simons, Jérôme R.
author_facet Simons, Jérôme R.
contents We generalise the inference procedure for eigenvectors of symmetrizable matrices of Tyler (1981) to that of invariant and singular subspaces of non-diagonalizable matrices. Wald tests for invariant vectors and $t$-tests for their individual coefficients perform well in simulations, despite the matrix being not symmetric. Using these results, it is now possible to perform inference on network statistics that depend on eigenvectors of non-symmetric adjacency matrices as they arise in empirical applications from directed networks. Further, we find that statisticians only need control over the first-order Davis-Kahan bound to control convergence rates of invariant subspace estimators to higher-orders. For general invariant subspaces, the minimal eigenvalue separation dominates the first-order bound potentially slowing convergence rates considerably. In an example, we find that accounting for uncertainty in network estimates changes empirical conclusions about the ranking of nodes' popularity.
format Preprint
id arxiv_https___arxiv_org_abs_2303_18233
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Hypothesis testing on invariant subspaces of non-diagonalizable matrices with applications to network statistics
Simons, Jérôme R.
Statistics Theory
Econometrics
Machine Learning
62
G.3
We generalise the inference procedure for eigenvectors of symmetrizable matrices of Tyler (1981) to that of invariant and singular subspaces of non-diagonalizable matrices. Wald tests for invariant vectors and $t$-tests for their individual coefficients perform well in simulations, despite the matrix being not symmetric. Using these results, it is now possible to perform inference on network statistics that depend on eigenvectors of non-symmetric adjacency matrices as they arise in empirical applications from directed networks. Further, we find that statisticians only need control over the first-order Davis-Kahan bound to control convergence rates of invariant subspace estimators to higher-orders. For general invariant subspaces, the minimal eigenvalue separation dominates the first-order bound potentially slowing convergence rates considerably. In an example, we find that accounting for uncertainty in network estimates changes empirical conclusions about the ranking of nodes' popularity.
title Hypothesis testing on invariant subspaces of non-diagonalizable matrices with applications to network statistics
topic Statistics Theory
Econometrics
Machine Learning
62
G.3
url https://arxiv.org/abs/2303.18233