Results 11 to 20 of about 772 (64)
A combinatorial expression for the group inverse of symmetric M-matrices
By using combinatorial techniques, we obtain an extension of the matrix-tree theorem for general symmetric M-matrices with no restrictions, this means that we do not have to assume the diagonally dominance hypothesis.
Carmona A., Encinas A.M., Mitjana M.
doaj +1 more source
Characterization of the Oblique Projector $U(VU)^+V$ with Application to Constrained Least Squares [PDF]
We provide a full characterization of the oblique projector $U(VU)^+V$ in the general case where the range of $U$ and the null space of $V$ are not complementary subspaces.
Aleš Černý+12 more
core +2 more sources
Diagonal dominance and invertibility of matrices
A weakly diagonally dominant matrix may or may not be invertible. We characterize, in terms of combinatorial structure and sign pattern when such a matrix is invertible, which is the common case. Examples are given.
Johnson Charles Royal+2 more
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On decompositions of estimators under a general linear model with partial parameter restrictions
A general linear model can be given in certain multiple partitioned forms, and there exist submodels associated with the given full model. In this situation, we can make statistical inferences from the full model and submodels, respectively.
Jiang Bo, Tian Yongge, Zhang Xuan
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The 𝔪-WG° inverse in the Minkowski space
In this article, we study the m{\mathfrak{m}}-WG∘{}^{\circ } inverse which presents a generalization of the m{\mathfrak{m}}-WG inverse in the Minkowski space. We first show the existence and the uniqueness of the generalized inverse.
Liu Xiaoji, Zhang Kaiyue, Jin Hongwei
doaj +1 more source
On mixed‐type reverse‐order laws for the Moore‐Penrose inverse of a matrix product
Some mixed‐type reverse‐order laws for the Moore‐Penrose inverse of a matrix product are established. Necessary and sufficient conditions for these laws to hold are found by the matrix rank method. Some applications and extensions of these reverse‐order laws to the weighted Moore‐Penrose inverse are also given.
Yongge Tian
wiley +1 more source
In this note, a new concept called {\em $SDR$-matrix} is proposed, which is an infinite lower triangular matrix obeying the generalized rule of David star.
Sun, Yidong
core +2 more sources
On the relation between Moore′s and Penrose′s conditions
Moore (1920) defined the reciprocal of any matrix over the complex field by three conditions, but the beauty of the definition was not realized until Penrose (1955) defined the same inverse using four conditions. The reciprocal is now often called the Moore-Penrose inverse, and has been widely used in various areas.
Gaoxiong Gan
wiley +1 more source
A note on computing the generalized inverse A T,S (2) of a matrix A
The generalized inverse A T,S (2) of a matrix A is a {2}‐inverse of A with the prescribed range T and null space S. A representation for the generalized inverse A T,S (2) has been recently developed with the condition σ (GA| T) ⊂ (0, ∞), where G is a matrix with R(G) = T andN(G) = S. In this note, we remove the above condition. Three types of iterative
Xiezhang Li, Yimin Wei
wiley +1 more source
On matrix convexity of the Moore‐Penrose inverse
Matrix convexity of the Moore‐Penrose inverse was considered in the recent literature. Here we give some converse inequalities as well as further generalizations.
B. Mond, J. E. Pečarić
wiley +1 more source