Saved in:
Bibliographic Details
Main Author: Zhang, Lucas Z.
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2508.09278
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909735463157760
author Zhang, Lucas Z.
author_facet Zhang, Lucas Z.
contents Motivated by the orthogonal series density estimation in $L^2([0,1],μ)$, in this project we consider a new class of functions that we call the approximate sparsity class. This new class is characterized by the rate of decay of the individual Fourier coefficients for a given orthonormal basis. We establish the $L^2([0,1],μ)$ metric entropy of such class, with which we show the minimax rate of convergence. For the density subset in this class, we propose an adaptive density estimator based on a hard-thresholding procedure that achieves this minimax rate up to a $\log$ term.
format Preprint
id arxiv_https___arxiv_org_abs_2508_09278
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Approximate Sparsity Class and Minimax Estimation
Zhang, Lucas Z.
Econometrics
Motivated by the orthogonal series density estimation in $L^2([0,1],μ)$, in this project we consider a new class of functions that we call the approximate sparsity class. This new class is characterized by the rate of decay of the individual Fourier coefficients for a given orthonormal basis. We establish the $L^2([0,1],μ)$ metric entropy of such class, with which we show the minimax rate of convergence. For the density subset in this class, we propose an adaptive density estimator based on a hard-thresholding procedure that achieves this minimax rate up to a $\log$ term.
title Approximate Sparsity Class and Minimax Estimation
topic Econometrics
url https://arxiv.org/abs/2508.09278