Hybrid ISTA: Unfolding ISTA With Convergence Guarantees Using Free-Form
Deep Neural Networks
- URL: http://arxiv.org/abs/2204.11640v1
- Date: Mon, 25 Apr 2022 13:17:57 GMT
- Title: Hybrid ISTA: Unfolding ISTA With Convergence Guarantees Using Free-Form
Deep Neural Networks
- Authors: Ziyang Zheng, Wenrui Dai, Duoduo Xue, Chenglin Li, Junni Zou, Hongkai
Xiong
- Abstract summary: It is promising to solve linear inverse problems by unfolding iterative algorithms as deep neural networks (DNNs) with learnable parameters.
Existing ISTA-based unfolded algorithms restrict the network architectures for iterative updates with the partial weight coupling structure to guarantee convergence.
This paper is the first to provide a convergence-provable framework that enables free-form DNNs in ISTA-based unfolded algorithms.
- Score: 50.193061099112626
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: It is promising to solve linear inverse problems by unfolding iterative
algorithms (e.g., iterative shrinkage thresholding algorithm (ISTA)) as deep
neural networks (DNNs) with learnable parameters. However, existing ISTA-based
unfolded algorithms restrict the network architectures for iterative updates
with the partial weight coupling structure to guarantee convergence. In this
paper, we propose hybrid ISTA to unfold ISTA with both pre-computed and learned
parameters by incorporating free-form DNNs (i.e., DNNs with arbitrary feasible
and reasonable network architectures), while ensuring theoretical convergence.
We first develop HCISTA to improve the efficiency and flexibility of classical
ISTA (with pre-computed parameters) without compromising the convergence rate
in theory. Furthermore, the DNN-based hybrid algorithm is generalized to
popular variants of learned ISTA, dubbed HLISTA, to enable a free architecture
of learned parameters with a guarantee of linear convergence. To our best
knowledge, this paper is the first to provide a convergence-provable framework
that enables free-form DNNs in ISTA-based unfolded algorithms. This framework
is general to endow arbitrary DNNs for solving linear inverse problems with
convergence guarantees. Extensive experiments demonstrate that hybrid ISTA can
reduce the reconstruction error with an improved convergence rate in the tasks
of sparse recovery and compressive sensing.
Related papers
- On the Convergence Analysis of Over-Parameterized Variational Autoencoders: A Neural Tangent Kernel Perspective [7.580900499231056]
Variational Auto-Encoders (VAEs) have emerged as powerful probabilistic models for generative tasks.
This paper provides a mathematical proof of VAE under mild assumptions.
We also establish a novel connection between the optimization problem faced by over-Eized SNNs and the Kernel Ridge (KRR) problem.
arXiv Detail & Related papers (2024-09-09T06:10:31Z) - Enhancing GNNs Performance on Combinatorial Optimization by Recurrent Feature Update [0.09986418756990156]
We introduce a novel algorithm, denoted hereafter as QRF-GNN, leveraging the power of GNNs to efficiently solve Combinatorial optimization (CO) problems.
It relies on unsupervised learning by minimizing the loss function derived from QUBO relaxation.
Results of experiments show that QRF-GNN drastically surpasses existing learning-based approaches and is comparable to the state-of-the-art conventionals.
arXiv Detail & Related papers (2024-07-23T13:34:35Z) - Regularized Adaptive Momentum Dual Averaging with an Efficient Inexact Subproblem Solver for Training Structured Neural Network [9.48424754175943]
We propose a Regularized Adaptive Momentum Dual Averaging (RAMDA) for training structured neural networks.
We show that RAMDA attains the ideal structure induced by the regularizer at the stationary point of convergence.
Experiments in large-scale modern computer vision, language modeling, and speech tasks show that the proposed RAMDA is efficient and consistently outperforms state of the art for training structured neural network.
arXiv Detail & Related papers (2024-03-21T13:43:49Z) - Stable Nonconvex-Nonconcave Training via Linear Interpolation [51.668052890249726]
This paper presents a theoretical analysis of linearahead as a principled method for stabilizing (large-scale) neural network training.
We argue that instabilities in the optimization process are often caused by the nonmonotonicity of the loss landscape and show how linear can help by leveraging the theory of nonexpansive operators.
arXiv Detail & Related papers (2023-10-20T12:45:12Z) - Stochastic Unrolled Federated Learning [85.6993263983062]
We introduce UnRolled Federated learning (SURF), a method that expands algorithm unrolling to federated learning.
Our proposed method tackles two challenges of this expansion, namely the need to feed whole datasets to the unrolleds and the decentralized nature of federated learning.
arXiv Detail & Related papers (2023-05-24T17:26:22Z) - Tree ensemble kernels for Bayesian optimization with known constraints
over mixed-feature spaces [54.58348769621782]
Tree ensembles can be well-suited for black-box optimization tasks such as algorithm tuning and neural architecture search.
Two well-known challenges in using tree ensembles for black-box optimization are (i) effectively quantifying model uncertainty for exploration and (ii) optimizing over the piece-wise constant acquisition function.
Our framework performs as well as state-of-the-art methods for unconstrained black-box optimization over continuous/discrete features and outperforms competing methods for problems combining mixed-variable feature spaces and known input constraints.
arXiv Detail & Related papers (2022-07-02T16:59:37Z) - Comparative Analysis of Interval Reachability for Robust Implicit and
Feedforward Neural Networks [64.23331120621118]
We use interval reachability analysis to obtain robustness guarantees for implicit neural networks (INNs)
INNs are a class of implicit learning models that use implicit equations as layers.
We show that our approach performs at least as well as, and generally better than, applying state-of-the-art interval bound propagation methods to INNs.
arXiv Detail & Related papers (2022-04-01T03:31:27Z) - Only Train Once: A One-Shot Neural Network Training And Pruning
Framework [31.959625731943675]
Structured pruning is a commonly used technique in deploying deep neural networks (DNNs) onto resource-constrained devices.
We propose a framework that DNNs are slimmer with competitive performances and significant FLOPs reductions by Only-Train-Once (OTO)
OTO contains two keys: (i) we partition the parameters of DNNs into zero-invariant groups, enabling us to prune zero groups without affecting the output; and (ii) to promote zero groups, we then formulate a structured-Image optimization algorithm, Half-Space Projected (HSPG)
To demonstrate the effectiveness of OTO, we train and
arXiv Detail & Related papers (2021-07-15T17:15:20Z) - Neurally Augmented ALISTA [15.021419552695066]
We introduce Neurally Augmented ALISTA, in which an LSTM network is used to compute step sizes and thresholds individually for each target vector during reconstruction.
We show that our approach further improves empirical performance in sparse reconstruction, in particular outperforming existing algorithms by an increasing margin as the compression ratio becomes more challenging.
arXiv Detail & Related papers (2020-10-05T11:39:49Z) - ACDC: Weight Sharing in Atom-Coefficient Decomposed Convolution [57.635467829558664]
We introduce a structural regularization across convolutional kernels in a CNN.
We show that CNNs now maintain performance with dramatic reduction in parameters and computations.
arXiv Detail & Related papers (2020-09-04T20:41:47Z)
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.