Bayesian Analysis
- Bayesian Anal.
- Volume 12, Number 4 (2017), 1105-1131.
The Horseshoe+ Estimator of Ultra-Sparse Signals
Anindya Bhadra, Jyotishka Datta, Nicholas G. Polson, and Brandon Willard
Abstract
We propose a new prior for ultra-sparse signal detection that we term the “horseshoe+ prior.” The horseshoe+ prior is a natural extension of the horseshoe prior that has achieved success in the estimation and detection of sparse signals and has been shown to possess a number of desirable theoretical properties while enjoying computational feasibility in high dimensions. The horseshoe+ prior builds upon these advantages. Our work proves that the horseshoe+ posterior concentrates at a rate faster than that of the horseshoe in the Kullback–Leibler (K-L) sense. We also establish theoretically that the proposed estimator has lower posterior mean squared error in estimating signals compared to the horseshoe and achieves the optimal Bayes risk in testing up to a constant. For one-group global–local scale mixture priors, we develop a new technique for analyzing the marginal sparse prior densities using the class of Meijer-G functions. In simulations, the horseshoe+ estimator demonstrates superior performance in a standard design setting against competing methods, including the horseshoe and Dirichlet–Laplace estimators. We conclude with an illustration on a prostate cancer data set and by pointing out some directions for future research.
Article information
Source
Bayesian Anal., Volume 12, Number 4 (2017), 1105-1131.
Dates
First available in Project Euclid: 22 September 2016
Permanent link to this document
https://projecteuclid.org/euclid.ba/1474572263
Digital Object Identifier
doi:10.1214/16-BA1028
Mathematical Reviews number (MathSciNet)
MR3724980
Zentralblatt MATH identifier
1384.62079
Subjects
Primary: 62F15: Bayesian inference
Secondary: 62F12: Asymptotic properties of estimators 62C10: Bayesian problems; characterization of Bayes procedures
Keywords
Bayesian global–local shrinkage horseshoe horseshoe+ normal means sparsity
Rights
Creative Commons Attribution 4.0 International License.
Citation
Bhadra, Anindya; Datta, Jyotishka; Polson, Nicholas G.; Willard, Brandon. The Horseshoe+ Estimator of Ultra-Sparse Signals. Bayesian Anal. 12 (2017), no. 4, 1105--1131. doi:10.1214/16-BA1028. https://projecteuclid.org/euclid.ba/1474572263
Supplemental materials
- Supplementary Material to “The Horseshoe+ Estimator of Ultra-Sparse Signals”. Contains the proofs of theorems and an additional simulation example.Digital Object Identifier: doi:10.1214/16-BA1028SUPP

