Variational Garrote for Sparse Inverse Problems
- URL: http://arxiv.org/abs/2603.12562v1
- Date: Fri, 13 Mar 2026 01:50:27 GMT
- Title: Variational Garrote for Sparse Inverse Problems
- Abstract summary: This work investigates the effect of sparsity priors in inverse problems by comparing conventional L1 regularization with the Variational Garrote (VG)<n>A unified experimental framework is constructed across multiple reconstruction tasks including signal resampling, signal denoising, and sparse-view computed tomography.
- Score: 1.1049501660241197
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Sparse regularization plays a central role in solving inverse problems arising from incomplete or corrupted measurements. Different regularizers correspond to different prior assumptions about the structure of the unknown signal, and reconstruction performance depends on how well these priors match the intrinsic sparsity of the data. This work investigates the effect of sparsity priors in inverse problems by comparing conventional L1 regularization with the Variational Garrote (VG), a probabilistic method that approximates L0 sparsity through variational binary gating variables. A unified experimental framework is constructed across multiple reconstruction tasks including signal resampling, signal denoising, and sparse-view computed tomography. To enable consistent comparison across models with different parameterizations, regularization strength is swept across wide ranges and reconstruction behavior is analyzed through train-generalization error curves. Experiments reveal characteristic bias-variance tradeoff patterns across tasks and demonstrate that VG frequently achieves lower minimum generalization error and improved stability in strongly underdetermined regimes where accurate support recovery is critical. These results suggest that sparsity priors closer to spike-and-slab structure can provide advantages when the underlying coefficient distribution is strongly sparse. The study highlights the importance of prior-data alignment in sparse inverse problems and provides empirical insights into the behavior of variational L0-type methods across different information bottlenecks.
Related papers
- Effective Covariance Dynamics in Solvable High-Dimensional GANs [2.639628765667673]
We study a solvable high-dimensional model of generative adversarial network (GAN) training in which a linear generator learns a low-dimensional subspace from data.<n>We prove that the microscopic training process converges, in the high-dimensional limit, to deterministic ordinary differential equations governed by this effective covariance.
arXiv Detail & Related papers (2026-06-25T16:33:54Z) - ROTI-GCV: Generalized Cross-Validation for right-ROTationally Invariant Data [5.830619388189558]
Two key tasks in high-dimensional regularized regression are tuning the regularization strength for accurate predictions and estimating the out-of-sample risk.<n>We introduce a new framework, ROTI-GCV, for reliably performing cross-validation under challenging conditions.
arXiv Detail & Related papers (2024-06-17T15:50:00Z) - Learning a Gaussian Mixture for Sparsity Regularization in Inverse Problems [2.174919458782602]
In inverse problems, the incorporation of a sparsity prior yields a regularization effect on the solution.<n>We propose a probabilistic sparsity prior formulated as a mixture of Gaussians, capable of modeling sparsity with respect to a generic basis.<n>We put forth both a supervised and an unsupervised training strategy to estimate the parameters of this network.
arXiv Detail & Related papers (2024-01-29T22:52:57Z) - GIT: Detecting Uncertainty, Out-Of-Distribution and Adversarial Samples
using Gradients and Invariance Transformations [77.34726150561087]
We propose a holistic approach for the detection of generalization errors in deep neural networks.
GIT combines the usage of gradient information and invariance transformations.
Our experiments demonstrate the superior performance of GIT compared to the state-of-the-art on a variety of network architectures.
arXiv Detail & Related papers (2023-07-05T22:04:38Z) - On the Double Descent of Random Features Models Trained with SGD [78.0918823643911]
We study properties of random features (RF) regression in high dimensions optimized by gradient descent (SGD)
We derive precise non-asymptotic error bounds of RF regression under both constant and adaptive step-size SGD setting.
We observe the double descent phenomenon both theoretically and empirically.
arXiv Detail & Related papers (2021-10-13T17:47:39Z) - Disentangling Generative Factors of Physical Fields Using Variational
Autoencoders [0.0]
This work explores the use of variational autoencoders (VAEs) for non-linear dimension reduction.
A disentangled decomposition is interpretable and can be transferred to a variety of tasks including generative modeling.
arXiv Detail & Related papers (2021-09-15T16:02:43Z) - Benign Overfitting of Constant-Stepsize SGD for Linear Regression [122.70478935214128]
inductive biases are central in preventing overfitting empirically.
This work considers this issue in arguably the most basic setting: constant-stepsize SGD for linear regression.
We reflect on a number of notable differences between the algorithmic regularization afforded by (unregularized) SGD in comparison to ordinary least squares.
arXiv Detail & Related papers (2021-03-23T17:15:53Z) - CASTLE: Regularization via Auxiliary Causal Graph Discovery [89.74800176981842]
We introduce Causal Structure Learning (CASTLE) regularization and propose to regularize a neural network by jointly learning the causal relationships between variables.
CASTLE efficiently reconstructs only the features in the causal DAG that have a causal neighbor, whereas reconstruction-based regularizers suboptimally reconstruct all input features.
arXiv Detail & Related papers (2020-09-28T09:49:38Z) - When Does Preconditioning Help or Hurt Generalization? [74.25170084614098]
We show how the textitimplicit bias of first and second order methods affects the comparison of generalization properties.
We discuss several approaches to manage the bias-variance tradeoff, and the potential benefit of interpolating between GD and NGD.
arXiv Detail & Related papers (2020-06-18T17:57:26Z) - Total Deep Variation: A Stable Regularizer for Inverse Problems [71.90933869570914]
We introduce the data-driven general-purpose total deep variation regularizer.
In its core, a convolutional neural network extracts local features on multiple scales and in successive blocks.
We achieve state-of-the-art results for numerous imaging tasks.
arXiv Detail & Related papers (2020-06-15T21:54:15Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.