activity
20122025
most citedSome matrix nearness problems suggested by Tikhonov regularization

22 citations · 78 across the 20 of their papers we have counts for

collaborators

23 papers

math.NA2025

Sensitivity of Perron and Fiedler eigenpairs to structural perturbations of a network

Silvia Noschese, Lothar Reichel

One can estimate the change of the Perron and Fiedler values for a connected network when the weight of an edge is perturbed by analyzing relevant entries of the Perron and Fiedler…

physics.soc-ph2025

Network connectivity analysis via shortest paths

Silvia Noschese, Lothar Reichel

Complex systems of interacting components often can be modeled by a simple graph that consists of a set of nodes and a set of edges. Such a graph can be repre…

math.NA2024

Communication in Multiplex Transportation Networks

Silvia Noschese, Lothar Reichel

Complex networks are made up of vertices and edges. The edges, which may be directed or undirected, are equipped with positive weights. Modeling complex systems that consist of dif…

math.NA2023

Enhancing multiplex global efficiency

Silvia Noschese, Lothar Reichel

Modeling complex systems that consist of different types of objects leads to multilayer networks, in which vertices are connected by both inter-layer and intra-layer edges. In this…

math.NA2023

Network analysis with the aid of the path length matrix

Silvia Noschese, Lothar Reichel

Let a network be represented by a simple graph with vertices. A common approach to investigate properties of a network is to use the adjacency matrix $A=[a_{ij}]_…

math.NA2022

A tensor formalism for multilayer network centrality measures using the Einstein product

Smahane El-Halouy, Silvia Noschese, Lothar Reichel

Complex systems that consist of different kinds of entities that interact in different ways can be modeled by multilayer networks. This paper uses the tensor formalism with the Ein…

math.NA2022

The structured distance to singularity of a symmetric tridiagonal Toeplitz matrix

Silvia Noschese

This paper is concerned with the distance of a symmetric tridiagonal Toeplitz matrix to the variety of similarly structured singular matrices, and with determining the closest…

math.NA2022★ 11 cited

Perron communicability and sensitivity of multilayer networks

Smahane El-Halouy, Silvia Noschese, Lothar Reichel

Modeling complex systems that consist of different types of objects leads to multilayer networks, where nodes in the different layers represent different kind of objects. Nodes are…

math.NA2022

On the banded Toeplitz structured distance to symmetric positive semidefiniteness

Silvia Noschese, Lothar Reichel

This paper is concerned with the determination of a close real banded positive definite Toeplitz matrix in the Frobenius norm to a given square real banded matrix. While it is stra…

math.NA2021

Communication in Complex Networks

Omar De la Cruz Cabrera, Jiafeng Jin, Silvia Noschese +1

One of the properties of interest in the analysis of networks is \emph{global communicability}, i.e., how easy or difficult it is, generally, to reach nodes from other nodes by fol…

math.NA2021

Estimating and increasing the structural robustness of a network

Silvia Noschese, Lothar Reichel

The capability of a network to cope with threats and survive attacks is referred to as its robustness. This paper discusses one kind of robustness, commonly denoted structural robu…

math.NA2020

Functions and eigenvectors of partially known matrices with applications to network analysis

Mohammed Al Mugahwi, Omar De la Cruz Cabrera, Silvia Noschese +1

Matrix functions play an important role in applied mathematics. In network analysis, in particular, the exponential of the adjacency matrix associated with a network provides valua…

math.NA2018★ 11 cited

A spectral method for bipartizing a network and detecting a large anti-community

A. Concas, S. Noschese, L. Reichel +1

Relations between discrete quantities such as people, genes, or streets can be described by networks, which consist of nodes that are connected by edges. Network analysis aims to i…

math.NA2018

Eigenvector sensitivity under general and structured perturbations of tridiagonal Toeplitz-type matrices

Silvia Noschese, Lothar Reichel

The sensitivity of eigenvalues of structured matrices under general or structured perturbations of the matrix entries has been thoroughly studied in the literature. Error bounds ar…

math.NA2018

Arnoldi decomposition, GMRES, and preconditioning for linear discrete ill-posed problems

Silvia Gazzola, Silvia Noschese, Paolo Novati +1

GMRES is one of the most popular iterative methods for the solution of large linear systems of equations that arise from the discretization of linear well-posed problems, such as D…

math.NA2017

Regularization matrices for discrete ill-posed problems in several space-dimensions

Laura Dykes, Guangxin Huang, Silvia Noschese +1

Many applications in science and engineering require the solution of large linear discrete ill-posed problems that are obtained by the discretization of a Fredholm integral equatio…

math.NA2017

Computing Unstructured and Structured Polynomial Pseudospectrum Approximations

Silvia Noschese, Lothar Reichel

In many applications it is important to understand the sensitivity of eigenvalues of a matrix polynomial to perturbations of the polynomial. The sensitivity commonly is described b…

math.NA2016

Approximated structured pseudospectra

Silvia Noschese, Lothar Reichel

Pseudospectra and structured pseudospectra are important tools for the analysis of matrices. Their computation, however, can be very demanding for all but small matrices. A new app…

math.NA2016

Circulant preconditioners for discrete ill-posed Toeplitz systems

L. Dykes, S. Noschese, L. Reichel

Circulant preconditioners are commonly used to accelerate the rate of convergence of iterative methods when solving linear systems of equations with a Toeplitz matrix. Block extens…

math.NA2016★ 22 cited

Regularization matrices determined by matrix nearness problems

Guangxin Huang, Silvia Noschese, Lothar Reichel

This paper is concerned with the solution of large-scale linear discrete ill-posed problems with error-contaminated data. Tikhonov regularization is a popular approach to determine…

math.NA2016★ 22 cited

Some matrix nearness problems suggested by Tikhonov regularization

Silvia Noschese, Lothar Reichel

The numerical solution of linear discrete ill-posed problems typically requires regularization, i.e., replacement of the available ill-conditioned problem by a nearby better condit…

math.NA2014★ 6 cited

Differential equations for real-structured (and unstructured) defectivity measures

Paolo Buttà, Nicola Guglielmi, Manuela Manetta +1

Let be either a complex or real matrix with all distinct eigenvalues. We propose a new method for the computation of both the unstructured and the real-structured (if the matri…

math.NA2012★ 6 cited

Structured conditioning of Hamiltonian eigenvalue problems

Paolo Buttà, Silvia Noschese

We discuss the effect of structure-preserving perturbations on complex or real Hamiltonian eigenproblems and characterize the structured worst-case effect perturbations. We derive…