Search Results for author: Esa Ollila

Found 14 papers, 5 papers with code

Greedy Capon Beamformer

no code implementations7 Apr 2024 Esa Ollila

We propose greedy Capon beamformer (GBF) for direction finding of narrow-band sources present in the array's viewing field.

Regularized EM algorithm

no code implementations27 Mar 2023 Pierre Houdouin, Esa Ollila, Frederic Pascal

We show that the theoretical guarantees of convergence hold, leading to better performing EM algorithm for structured covariance matrix models or with low sample settings.

Graph Neural Network Sensitivity Under Probabilistic Error Model

no code implementations15 Mar 2022 Xinjue Wang, Esa Ollila, Sergiy A. Vorobyov

In this paper, we study the effect of a probabilistic graph error model on the performance of the GCNs.

Coupled Feature Learning for Multimodal Medical Image Fusion

1 code implementation17 Feb 2021 Farshad G. Veshki, Nora Ouzir, Sergiy A. Vorobyov, Esa Ollila

The resulting performance and execution times show the competitiveness of the proposed method in comparison with state-of-the-art medical image fusion methods.

Dictionary Learning

Coupled regularized sample covariance matrix estimator for multiple classes

no code implementations9 Nov 2020 Elias Raninen, Esa Ollila

In this work, we consider regularized SCM (RSCM) estimators for multiclass problems that couple together two different target matrices for regularization: the pooled (average) SCM of the classes and the scaled identity matrix.

Block-wise Minimization-Majorization algorithm for Huber's criterion: sparse learning and applications

1 code implementation25 Aug 2020 Esa Ollila, Ammar Mian

Huber's criterion can be used for robust joint estimation of regression and scale parameters in the linear model.

Image Denoising Sparse Learning

Linear pooling of sample covariance matrices

1 code implementation13 Aug 2020 Elias Raninen, David E. Tyler, Esa Ollila

We consider the problem of estimating high-dimensional covariance matrices of $K$-populations or classes in the setting where the sample sizes are comparable to the data dimension.

Methodology

A Compressive Classification Framework for High-Dimensional Data

no code implementations9 May 2020 Muhammad Naveed Tabassum, Esa Ollila

We propose a compressive classification framework for settings where the data dimensionality is significantly higher than the sample size.

Classification feature selection +2

M-estimators of scatter with eigenvalue shrinkage

no code implementations12 Feb 2020 Esa Ollila, Daniel P. Palomar, Frederic Pascal

A popular regularized (shrinkage) covariance estimator is the shrinkage sample covariance matrix (SCM) which shares the same set of eigenvectors as the SCM but shrinks its eigenvalues toward its grand mean.

Simultaneous Signal Subspace Rank and Model Selection with an Application to Single-snapshot Source Localization

1 code implementation19 Jun 2018 Muhammad Naveed Tabassum, Esa Ollila

This paper proposes a novel method for model selection in linear regression by utilizing the solution path of $\ell_1$ regularized least-squares (LS) approach (i. e., Lasso).

Methodology Complex Variables Optimization and Control Applications

Sequential adaptive elastic net approach for single-snapshot source localization

1 code implementation19 May 2018 Muhammad Naveed Tabassum, Esa Ollila

This paper proposes efficient algorithms for accurate recovery of direction-of-arrival (DoA) of sources from single-snapshot measurements using compressed beamforming (CBF).

Compressive Regularized Discriminant Analysis of High-Dimensional Data with Applications to Microarray Studies

no code implementations11 Apr 2018 Muhammad Naveed Tabassum, Esa Ollila

We propose a modification of linear discriminant analysis, referred to as compressive regularized discriminant analysis (CRDA), for analysis of high-dimensional datasets.

feature selection

Multichannel sparse recovery of complex-valued signals using Huber's criterion

no code implementations16 Apr 2015 Esa Ollila

In this paper, we generalize Huber's criterion to multichannel sparse recovery problem of complex-valued measurements where the objective is to find good recovery of jointly sparse unknown signal vectors from the given multiple measurement vectors which are different linear combinations of the same known elementary vectors.

regression

Robust, scalable and fast bootstrap method for analyzing large scale data

no code implementations9 Apr 2015 Shahab Basiri, Esa Ollila, Visa Koivunen

In this paper we address the problem of performing statistical inference for large scale data sets i. e., Big Data.

Cannot find the paper you are looking for? You can Submit a new open access paper.