Results 11 to 20 of about 23,557 (176)
Existence of Moore-Penrose inverses in rings with involution [PDF]
We give necessary and sufficient conditions for the existence of the Moore-Penrose inverse of an element in a ring with involution. If R is a ring with involution, we also investigate the existence of the Moore-Penrose inverse of the product 1 2 n x
Wannisa Apairat, Sompong Chuysurichay
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The computation of the Moore–Penrose generalized inverse is a commonly used operation in various fields such as the training of neural networks based on random weights.
Elkin Gelvez-Almeida +3 more
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Calculating the Moore–Penrose Generalized Inverse on Massively Parallel Systems
In this work, we consider the problem of calculating the generalized Moore–Penrose inverse, which is essential in many applications of graph theory.
Vukašin Stanojević +4 more
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A Neural Network for Moore–Penrose Inverse of Time-Varying Complex-Valued Matrices
The Moore–Penrose inverse of a matrix plays a very important role in practical applications. In general, it is not easy to immediately solve the Moore–Penrose inverse of a matrix, especially for solving the Moore–Penrose inverse of a complex-valued ...
Yiyuan Chai +4 more
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On the mean and variance of the estimated tangency portfolio weights for small samples
In this paper, a sample estimator of the tangency portfolio (TP) weights is considered. The focus is on the situation where the number of observations is smaller than the number of assets in the portfolio and the returns are i.i.d.
Gustav Alfelt, Stepan Mazur
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The dual index and dual core generalized inverse
In this article, we introduce the dual index and dual core generalized inverse (DCGI). By applying rank equation, generalized inverse, and matrix decomposition, we give several characterizations of the dual index when it is equal to 1. We realize that if
Wang Hongxing, Gao Ju
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The Moore-Penrose inverse of differences and products of projectors in a ring with involution [PDF]
In this paper, we study the Moore–Penrose inverses of differences and products of projectors in a ring with involution. Some necessary and sufficient conditions for the existence of the Moore–Penrose inverse are given.
Chen, Jianlong +2 more
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Minimal Rank Properties of Outer Inverses with Prescribed Range and Null Space
The purpose of this paper is to investigate solvability of systems of constrained matrix equations in the form of constrained minimization problems.
Dijana Mosić +2 more
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Idempotent operator and its applications in Schur complements on Hilbert C*-module
The present study proves that TT is an idempotent operator if and only if R(I−T∗)⊕R(T)=X{\mathcal{ {\mathcal R} }}\left(I-{T}^{\ast })\oplus {\mathcal{ {\mathcal R} }}\left(T)={\mathcal{X}} and (T∗T)†=(T†)2T{\left({T}^{\ast }T)}^{\dagger }={\left({T ...
Karizaki Mehdi Mohammadzadeh +1 more
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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.
Gaoxiong Gan
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