An Alternating Direction Method of Multipliers Algorithm for the Weighted Fused LASSO Signal Approximator

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Dijkstra, Louis, Hanke, Moritz, Koenen, Niklas, Foraita, Ronja
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913445821022208
author Dijkstra, Louis
Hanke, Moritz
Koenen, Niklas
Foraita, Ronja
author_facet Dijkstra, Louis
Hanke, Moritz
Koenen, Niklas
Foraita, Ronja
contents We present an Alternating Direction Method of Multipliers (ADMM) algorithm designed to solve the Weighted Generalized Fused LASSO Signal Approximator (wFLSA). First, we show that wFLSAs can always be reformulated as a Generalized LASSO problem. With the availability of algorithms tailored to the Generalized LASSO, the issue appears to be, in principle, resolved. However, the computational complexity of these algorithms is high, with a time complexity of $O(p^4)$ for a single iteration, where $p$ represents the number of coefficients. To overcome this limitation, we propose an ADMM algorithm specifically tailored for wFLSA-equivalent problems, significantly reducing the complexity to $O(p^2)$. Our algorithm is publicly accessible through the R package wflsa.
format Preprint
id arxiv_https___arxiv_org_abs_2407_18077
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle An Alternating Direction Method of Multipliers Algorithm for the Weighted Fused LASSO Signal Approximator
Dijkstra, Louis
Hanke, Moritz
Koenen, Niklas
Foraita, Ronja
Methodology
We present an Alternating Direction Method of Multipliers (ADMM) algorithm designed to solve the Weighted Generalized Fused LASSO Signal Approximator (wFLSA). First, we show that wFLSAs can always be reformulated as a Generalized LASSO problem. With the availability of algorithms tailored to the Generalized LASSO, the issue appears to be, in principle, resolved. However, the computational complexity of these algorithms is high, with a time complexity of $O(p^4)$ for a single iteration, where $p$ represents the number of coefficients. To overcome this limitation, we propose an ADMM algorithm specifically tailored for wFLSA-equivalent problems, significantly reducing the complexity to $O(p^2)$. Our algorithm is publicly accessible through the R package wflsa.
title An Alternating Direction Method of Multipliers Algorithm for the Weighted Fused LASSO Signal Approximator
topic Methodology
url https://arxiv.org/abs/2407.18077