In this paper, we mainly use the properties of the minimum eigenvalue of the Fan product of $M$-matrices and Cauchy-Schwarz inequality, and propose some new bounds for the minimum eigenvalue of the Fan product of two $M$-matrices. These results involve the maximum absolute value of off-diagonal entries of each row. Hence, the lower bounds for the minimum eigenvalue are easily calculated in the practical examples. In theory, a comparison is given in this paper. Finally, to illustrate our results, a simple...

We prove that the principal eigenvector of a positive matrix represents the relative dominance of its rows or ranking of alternatives in a decision represented by the rows of a pairwise comparison matrix.

Soit $\beta$ un nombre de Pisot ; nous montrons que pour tout entier $n$ assez grand il existe une matrice carrée à coefficients positifs ou nuls dont l’ordre est égal au degré de $\beta$ et dont ${\beta }^n$ est valeur propre.Soit $\beta =a_1/\beta +a_2/{\beta }^2+\cdots +a_n/{\beta }^n+\cdots$ le $\beta$-développement de $\beta$ ; si $\beta$ est un nombre de Pisot, alors la suite ${\left(a_n\right)}_{n\ge 1}$ est périodique après un certain rang $n_0$ (pour $n\ge n_0$, $a_{n+k}=a_n$) et le polynôme$$X^{n_0+k}-(a_1{X}^{n_0+k-1}+\cdots +a_{n_0+k})-(X^{n_0}-(a_1{X}^{n_0}+\cdots +a_{n_0}))$$est appelé polynôme de Parry. Nous montrons qu’il existe un ensemble relativement dense d’entiers $n$ tels que le polynôme minimal de ${\beta }^n$ est égal à son polynôme...

Four applications are outlined of pseudospectra of highly nonnormal linear operators.

We prove that if F is a Lipschitz map from the set of all complex n × n matrices into itself with F(0) = 0 such that given any x and y we know that F(x) - F(y) and x-y have at least one common eigenvalue, then either $F\left(x\right)=ux{u}^{-1}$ or $F\left(x\right)=u{x}^t{u}^{-1}$ for all x, for some invertible n × n matrix u. We arrive at the same conclusion by supposing F to be of class ¹ on a domain in ℳₙ containing the null matrix, instead of Lipschitz. We also prove that if F is of class ¹ on a domain containing the null matrix satisfying F(0) = 0...

This paper determines all nonsingular unicyclic mixed graphs on at least nine vertices with at most three Laplacian eigenvalues greater than two.

For a simple graph $G$ on $n$ vertices and an integer $k$ with $1\le k\le n$, denote by ${𝒮}_k^{+}\left(G\right)$ the sum of $k$ largest signless Laplacian eigenvalues of $G$. It was conjectured that ${𝒮}_k^{+}\left(G\right)\le e\left(G\right)+\left(\genfrac{}{}{0pt}{}{k+1}{2}\right)$, where $e\left(G\right)$ is the number of edges of $G$. This conjecture has been proved to be true for all graphs when $k\in \{1,2,n-1,n\}$, and for trees, unicyclic graphs, bicyclic graphs and regular graphs (for all $k$). In this note, this conjecture is proved to be true for all graphs when $k=n-2$, and for some new classes of graphs.

The purpose of this paper is to present a modern approach to the analysis of variance (ANOVA) of disconnected resolvable group divisible partially balanced incomplete block (GDPBIB) designs with factorial structure and with some interaction effects completely confounded. A characterization of a factorial experiment with completely confounded interaction is given. The treatment effect estimators and some relations between the matrix F of the reduced normal equations and the information matrix A are...