Research
On-device research index

arXiv research

A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

169,181 papers · 148 categories

Trend · papers per month

36912 · Oct 201919922001200920182026
48 results for Over-complete Dictionary

Paper presents a new method for efficient deep learning with over-complete dictionaries.

problem Learning an over-complete basis for optimal reconstruction without optimization.
method Multiscale Residual Mixture of PCA with a hierarchical approach.
result Exponential decrease of error with depth in a recursive deep approach.

New algorithm recovers dictionaries with arbitrary supports in polynomial time.

problem Learning dictionaries with arbitrary supports in polynomial time.
method Semirandom model with a mix of arbitrary and random supports; polynomial time algorithm.
result Polynomial time recovery of incoherent over-complete dictionaries with arbitrary supports.

Paper proposes a method to solve sparse Bayesian learning problems efficiently.

problem Finding sparsest solutions in high-dimensional settings.
method Sparse Bayesian learning with screening test to identify and remove zero coefficients.
result The method accelerates the solution process for sparse Bayesian learning problems.

Dictionary learning is a cutting-edge area in imaging processing, that has recently led to state-of-the-art results in many signal processing tasks. The idea is to conduct a linear decomposition of a signal using a few atoms of a learned and usually over-completed dictionary instead of a pre-defined basis. Determining …

2016-05-25abs ↗pdf ↗

Learning an encoding of feature vectors in terms of an over-complete dictionary or a information geometric (Fisher vectors) construct is wide-spread in statistical signal processing and computer vision. In content based information retrieval using deep-learning classifiers, such encodings are learnt on the flattened la…

2017-03-18abs ↗pdf ↗

A popular approach within the signal processing and machine learning communities consists in modelling signals as sparse linear combinations of atoms selected from a learned dictionary. While this paradigm has led to numerous empirical successes in various fields ranging from image to audio processing, there have only …

2014-07-19abs ↗pdf ↗

The power of sparse signal modeling with learned over-complete dictionaries has been demonstrated in a variety of applications and fields, from signal processing to statistical inference and machine learning. However, the statistical properties of these models, such as under-fitting or over-fitting given sets of data, …

2011-10-11abs ↗pdf ↗

This paper improves 3D pose recovery from 2D images using non-convex regularization.

problem 3D object pose recovery from 2D images.
method Proposes non-convex regularization with leaky capped ℓ1-norm (LCNR) and multi-stage optimization.
result Theoretical analysis shows estimation error decreases with optimization stages.

Sparse representations have proven their efficiency in solving a wide class of inverse problems encountered in signal and image processing. Conversely, enforcing the information to be spread uniformly over representation coefficients exhibits relevant properties in various applications such as digital communications. A…

2015-12-18abs ↗pdf ↗

We study Fredholm properties and index formulas for Dirac operators over complete Riemannian manifolds with straight ends. An important class of examples of such manifolds are complete Riemannian manifolds with pinched negative sectional curvature and finite volume.

2010-11-10abs ↗pdf ↗

DeepCAM learns convolutional dictionaries for image processing.

problem Processing high-dimensional signals like images efficiently.
method Introduces a Deep Convolutional Analysis Dictionary Model (DeepCAM) using convolutional dictionaries.
result DeepCAM achieves performance comparable to other methods on single image super-resolution.

Bayesian method improves dictionary learning for complex problems.

problem Efficiently identifying relevant dictionary entries for complex inverse problems.
method Bayesian group sparsity coding and deflation steps to compress and identify relevant subdictionaries.
result Significant computational complexity reduction and improved glitch detection in LIGO experiment.

Paper improves dictionary learning by addressing local and global coherence issues.

problem Improving dictionary learning by addressing local and global coherence issues.
method The paper uses the ITKrM algorithm to prove contraction under relaxed conditions and proposes replacing bad dictionaries with carefully designed candidates.
result The adaptive version of ITKrM can recover a generating dictionary from randomly initialized dictionaries of various sizes and learn meaningful dictionaries on image data.

This work learns sparse tensor representations using mixtures of separable dictionaries.

problem Learning sparse representations of tensor data with structured models.
method Proposes and explores learning a mixture of separable dictionaries with sufficient conditions for local identifiability.
result Developed computational algorithms for batch and online learning.

We present a two-stage approach for learning dictionaries for object classification tasks based on the principle of information maximization. The proposed method seeks a dictionary that is compact, discriminative, and generative. In the first stage, dictionary atoms are selected from an initial dictionary by maximizing…

2012-08-17abs ↗pdf ↗

Many techniques in computer vision, machine learning, and statistics rely on the fact that a signal of interest admits a sparse representation over some dictionary. Dictionaries are either available analytically, or can be learned from a suitable training set. While analytic dictionaries permit to capture the global st…

2013-03-21abs ↗pdf ↗

Sparse codes improve optimal control tasks with correlated inputs.

problem Optimal control tasks with correlated feature inputs.
method Used a sparse code to represent natural images in an optimal control task solved with neuro-dynamic programming.
result An over-complete sparse code increases memory capacity and learning speed beyond a complete code.

CRsAE auto-encoder recovers convolutional dictionary from noisy signals.

problem Recovering a convolutional dictionary from noisy signals.
method Constrained recurrent sparse auto-encoder (CRsAE) architecture.
result CRsAE successfully recovers the underlying dictionary in the presence of noise.

Paper provides conditions for local recovery of tensor data's Kronecker-structured dictionaries.

problem Local recovery of Kronecker-structured dictionaries for tensor data.
method Derives sufficient conditions for local recovery of coordinate dictionaries.
result Sufficient conditions guarantee recovery of individual coordinate dictionaries up to specified error.

Sparse coding in learned dictionaries has been established as a successful approach for signal denoising, source separation and solving inverse problems in general. A dictionary learning method adapts an initial dictionary to a particular signal class by iteratively computing an approximate factorization of a training …

2012-05-28abs ↗pdf ↗

Study shows unique sharp local minimum in 1\ell_1-minimization for dictionary learning.

problem Global recovery of a dictionary from random linear combinations of atoms.
method Norm condition, explicit bound, perturbation-based test, Block Coordinate Descent algorithm.
result Reference dictionary is the unique sharp local minimum of the 1\ell_1 objective function.

Researchers find optimal dictionaries for minimizing average squared coefficients in random vector representations.

problem Finding optimal dictionaries for minimizing the average squared coefficients in random vector representations.
method Using rank-1 decompositions and majorization theory, the study provides a complete characterization of optimal dictionaries.
result Complete characterization of 2\ell_2-optimal dictionaries with polynomial time algorithms.

In sparse signal representation, the choice of a dictionary often involves a tradeoff between two desirable properties -- the ability to adapt to specific signal data and a fast implementation of the dictionary. To sparsely represent signals residing on weighted graphs, an additional design challenge is to incorporate …

2014-01-05abs ↗pdf ↗

Sparse representations using learned dictionaries are being increasingly used with success in several data processing and machine learning applications. The availability of abundant training data necessitates the development of efficient, robust and provably good dictionary learning algorithms. Algorithmic stability an…

2013-03-03abs ↗pdf ↗

The paper provides guarantees for an alternating minimization algorithm in dictionary learning.

problem Dictionary learning problem of factorizing samples into a basis and sparse vectors.
method Alternating minimization procedure switching between 1\ell_1 minimization and gradient descent.
result Local convergence guarantees for the alternating minimization algorithm under a new matrix infinity norm condition.

The paper tackles dictionary learning with almost sure error constraints.

problem Achieving desirable features in data representation with almost sure error constraints.
method Imposes almost sure recovery constraints and reformulates the problem as a convex-concave min-max problem, solved using gradient descent-ascent.
result Demonstrates the effectiveness of the proposed method in achieving almost sure error constraints in dictionary learning.

We study the Dictionary Learning (aka Sparse Coding) problem of obtaining a sparse representation of data points, by learning \emph{dictionary vectors} upon which the data points can be written as sparse linear combinations. We view this problem from a geometry perspective as the spanning set of a subspace arrangement,…

2014-02-28abs ↗pdf ↗

The paper proposes a method to learn discriminative multilevel dictionaries for supervised image classification.

problem Improving sparse representation for supervised image classification.
method Learning structured multilevel dictionaries with discriminative constraints for each class, using reconstruction errors of image patches.
result Competitive results compared to state-of-the-art methods on texture image classification.

Dictionaries are collections of vectors used for representations of random vectors in Euclidean spaces. Recent research on optimal dictionaries is focused on constructing dictionaries that offer sparse representations, i.e., 0\ell_0-optimal representations. Here we consider the problem of finding optimal dictionaries …

2016-03-07abs ↗pdf ↗

This article addresses the issue of representing electroencephalographic (EEG) signals in an efficient way. While classical approaches use a fixed Gabor dictionary to analyze EEG signals, this article proposes a data-driven method to obtain an adapted dictionary. To reach an efficient dictionary learning, appropriate s…

2013-03-04abs ↗pdf ↗

The kernel least-mean-square (KLMS) algorithm is an appealing tool for online identification of nonlinear systems due to its simplicity and robustness. In addition to choosing a reproducing kernel and setting filter parameters, designing a KLMS adaptive filter requires to select a so-called dictionary in order to get a…

2013-10-31abs ↗pdf ↗