W-Kernel and Its Principal Space for Frequentist Evaluation of Bayesian Estimators

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
1. Verfasser: Iba, Yukito
Format: Preprint
Veröffentlicht: 2023
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866915550141087744
author Iba, Yukito
author_facet Iba, Yukito
contents Evaluating the variability of posterior estimates is a key aspect of Bayesian model assessment. In this study, we focus on the posterior covariance matrix W, defined through the log-likelihoods of individual observations. Previous studies, notably MacEachern and Peruggia(2002) and Thomas et al.(2018), examined the role of the principal space of W in Bayesian sensitivity analysis. Here, we show that the principal space of W is also central to frequentist evaluation, using the recently proposed Bayesian infinitesimal jackknife (Bayesian IJ) approximation (Giordano and Broderick(2023)) as a key tool. We further clarify the relationship between W and the Fisher kernel, showing that a modified version of the Fisher kernel can be viewed as an approximation to W. Moreover, the matrix W itself can be interpreted as a reproducing kernel, which we refer to as the W-kernel. Based on this connection, we investigate the relation between the W-kernel formulation in the data space and the classical asymptotic formulation in the parameter space. We also introduce the matrix Z, which is effectively dual to W in the sense of PCA; this formulation provides another perspective on the relationship between W and the classical asymptotic theory. In the appendices, we explore approximate bootstrap methods for posterior means and show that projection onto the principal space of W facilitates frequentist evaluation when higher-order terms are included. In addition, we introduce incomplete Cholesky decomposition as an efficient method for computing the principal space of W, and discuss the concept of representative subsets of observations.
format Preprint
id arxiv_https___arxiv_org_abs_2311_13017
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle W-Kernel and Its Principal Space for Frequentist Evaluation of Bayesian Estimators
Iba, Yukito
Methodology
Statistical Mechanics
Machine Learning
Evaluating the variability of posterior estimates is a key aspect of Bayesian model assessment. In this study, we focus on the posterior covariance matrix W, defined through the log-likelihoods of individual observations. Previous studies, notably MacEachern and Peruggia(2002) and Thomas et al.(2018), examined the role of the principal space of W in Bayesian sensitivity analysis. Here, we show that the principal space of W is also central to frequentist evaluation, using the recently proposed Bayesian infinitesimal jackknife (Bayesian IJ) approximation (Giordano and Broderick(2023)) as a key tool. We further clarify the relationship between W and the Fisher kernel, showing that a modified version of the Fisher kernel can be viewed as an approximation to W. Moreover, the matrix W itself can be interpreted as a reproducing kernel, which we refer to as the W-kernel. Based on this connection, we investigate the relation between the W-kernel formulation in the data space and the classical asymptotic formulation in the parameter space. We also introduce the matrix Z, which is effectively dual to W in the sense of PCA; this formulation provides another perspective on the relationship between W and the classical asymptotic theory. In the appendices, we explore approximate bootstrap methods for posterior means and show that projection onto the principal space of W facilitates frequentist evaluation when higher-order terms are included. In addition, we introduce incomplete Cholesky decomposition as an efficient method for computing the principal space of W, and discuss the concept of representative subsets of observations.
title W-Kernel and Its Principal Space for Frequentist Evaluation of Bayesian Estimators
topic Methodology
Statistical Mechanics
Machine Learning
url https://arxiv.org/abs/2311.13017