We study the conceptmatrix majorization: for two real matrices A and B having m rows we say that A majorizes B if there is a row-stochastic matrix X with AX = B. A special case is classical notion of vector majorization. Several properties and characterizations of matrix majorization are given. Moreover, interpretations of the concept in mathematical statistics are discussed and some combinator...

A Laplacian matrix, L = (lij) ∈ R , has nonpositive off-diagonal entries and zero row sums. As a matrix associated with a weighted directed graph, it generalizes the Laplacian matrix of an ordinary graph. A standardized Laplacian matrix is a Laplacian matrix with − 1 n ≤ lij ≤ 0 at j 6= i. We study the spectra of Laplacian matrices and relations between Laplacian matrices and stochastic matrice...

Let p be a homogeneous polynomial of degree n in n variables, p(z1, . . . , zn) = p(Z), Z ∈ C. We call such a polynomial p H-Stable if p(z1, . . . , zn) 6= 0 provided the real parts Re(zi) > 0, 1 ≤ i ≤ n. This notion from Control Theory is closely related to the notion of Hyperbolicity used intensively in the PDE theory. The main theorem in this paper states that if p(x1, . . . , xn) is a homog...

In this paper, we obtain expressions for the principal angles between the row spaces of input and output data block Hankel matrices of a linear stochastic model in terms of the model parameters. The canonical correlations of the corresponding processes are equal to the limiting values of the cosines of the principal angles. From these parametric expressions, the relations between the different ...

The Birkhoff (permutation) polytope, Bn, consists of the n × n nonnegative doubly stochastic matrices, has dimension (n− 1)2, and has n2 facets. A new analogue, the alternating sign matrix polytope, ASMn, is introduced and characterized. Its vertices are the Qn−1 j=0 (3j+1)! (n+j)! n × n alternating sign matrices. It has dimension (n− 1)2, has 4[(n− 2)2 +1] facets, and has a simple inequality d...

Let V be a vector space of dimension n over a fieldK of characteristic equal to 0 or ≥ n/2. Let g = gln(V ) and n be the nilcone of g, i.e., the cone of nilpotent matrices of g. We write elements of V and V ∗ as column and row vectors, respectively. In this paper we study the variety N := {(X,Y, i, j) ∈ n× n × V × V ∗ | [X,Y ] + ij = 0} and prove that it has n irreducible components: 2 of dimen...

We study the averaging-based distributed optimization solvers over random networks. show a general result on convergence of such schemes using weight-matrices that are row-stochastic almost surely and column-stochastic in expectation for broad class dependent weight-matrix sequences. In addition to implying many previously known results this domain, our work shows robustness link-failure. Also,...