Title
Algorithmic Analysis and Statistical Estimation of SLOPE via Approximate Message Passing
Abstract
SLOPE is a relatively new convex optimization procedure for high-dimensional linear regression via the sorted ℓ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> penalty: the larger the rank of the fitted coefficient, the larger the penalty. This non-separable penalty renders many existing techniques invalid or inconclusive in analyzing the SLOPE solution. In this paper, we develop an asymptotically exact characterization of the SLOPE solution under Gaussian random designs through solving the SLOPE problem using approximate message passing (AMP). This algorithmic approach allows us to approximate the SLOPE solution via the much more amenable AMP iterates. Explicitly, we characterize the asymptotic dynamics of the AMP iterates relying on a recently developed state evolution analysis for non-separable penalties, thereby overcoming the difficulty caused by the sorted ℓ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> penalty. Moreover, we prove that the AMP iterates converge to the SLOPE solution in an asymptotic sense, and numerical simulations show that the convergence is surprisingly fast. Our proof rests on a novel technique that specifically leverages the SLOPE problem. In contrast to prior literature, our work not only yields an asymptotically sharp analysis but also offers an algorithmic, flexible, and constructive approach to understanding the SLOPE problem.
Year
DOI
Venue
2019
10.1109/TIT.2020.3025272
IEEE Transactions on Information Theory
Keywords
Field
DocType
Approximate message passing (AMP),sorted ℓ₁ regression,high-dimensional regression,state evolution
Mathematical optimization,Computer science,Algorithm,Message passing
Conference
Volume
Issue
ISSN
67
1
0018-9448
Citations 
PageRank 
References 
1
0.36
0
Authors
4
Name
Order
Citations
PageRank
Bu, Zhiqi111.37
Jason M. Klusowski263.83
Cynthia Rush3267.81
Weijie Su48611.84