Saved in:
Bibliographic Details
Main Authors: Yin, Yanqing, Zhou, Wang
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2408.13848
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908910756036608
author Yin, Yanqing
Zhou, Wang
author_facet Yin, Yanqing
Zhou, Wang
contents In high-dimensional principal component analysis, important inferential targets include both leading spikes and the associated principal eigenspaces. Such problems arise naturally in high-dimensional factor models, where leading principal directions are interpreted as dominant loading directions and spike magnitudes reflect the strength of the corresponding common factors. We study inference based on the sample covariance matrix $\bS$ and the sample correlation matrix $\widehat{\bR}$ under generalized spiked models with arbitrary bulk spectrum. We establish almost sure limits and central limit theorems for spiked sample eigenvalues, and derive asymptotic distributions for functionals of sample spiked eigenspaces. Building on this theory, we develop procedures for one-sample inference for benchmark principal directions and for two-sample comparison of leading spike strengths across populations. Even in the covariance setting, our results substantially extend the existing literature by allowing a non-identity bulk structure. A real-data analysis on stock returns further illustrates the practical relevance of the proposed procedures, showing that covariance-based and correlation-based PCA can lead to markedly different conclusions.
format Preprint
id arxiv_https___arxiv_org_abs_2408_13848
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Inference for Spiked Eigenstructure under Generalized Covariance and Correlation Models
Yin, Yanqing
Zhou, Wang
Statistics Theory
In high-dimensional principal component analysis, important inferential targets include both leading spikes and the associated principal eigenspaces. Such problems arise naturally in high-dimensional factor models, where leading principal directions are interpreted as dominant loading directions and spike magnitudes reflect the strength of the corresponding common factors. We study inference based on the sample covariance matrix $\bS$ and the sample correlation matrix $\widehat{\bR}$ under generalized spiked models with arbitrary bulk spectrum. We establish almost sure limits and central limit theorems for spiked sample eigenvalues, and derive asymptotic distributions for functionals of sample spiked eigenspaces. Building on this theory, we develop procedures for one-sample inference for benchmark principal directions and for two-sample comparison of leading spike strengths across populations. Even in the covariance setting, our results substantially extend the existing literature by allowing a non-identity bulk structure. A real-data analysis on stock returns further illustrates the practical relevance of the proposed procedures, showing that covariance-based and correlation-based PCA can lead to markedly different conclusions.
title Inference for Spiked Eigenstructure under Generalized Covariance and Correlation Models
topic Statistics Theory
url https://arxiv.org/abs/2408.13848