Results 61 to 70 of about 463,715 (164)
Shifted model spaces and their orthogonal decompositions [PDF]
Opuscula MathematicaWe generalize certain well known orthogonal decompositions of model spaces and obtain similar decompositions for the wider class of shifted model spaces, allowing us to establish conditions for near invariance of the latter with respect to certain ...
M. Cristina Câmara +2 more
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A Quantised Push‐Sum Distributed Adaptive Momentum Algorithm for Optimisation Over Directed Networks
CAAI Transactions on Intelligence Technology, Volume 11, Issue 4, Page 1284-1301, August 2026.ABSTRACT In this paper, we investigate a distributed constrained optimisation problem over directed networks. The agents in the networks conduct local computations and communications, endeavouring to collaboratively minimise the aggregation of all locally known convex cost functions subject to a global constraint set.
Qingguo Lü +6 more
wiley +1 more source
The numerical range of a Toeplitz operator
, 1972 In this paper we explicitly compute the numerical range of an arbitrary Toeplitz operator on the classical Hardy space H 2 {H^2} of the unit circle.
E. M. Klein
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Composition operator induced by ?(z) = sz + t for which |s|?1, |t|<1 and |s|+|t|?1
مجلة بغداد للعلوم, 2010 We study in this paper the composition operator that is induced by ?(z) = sz + t. We give a characterization of the adjoint of composiotion operators generated by self-maps of the unit ball of form ?(z) = sz + t for which |s|?1, |t|
Baghdad Science Journal
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The Mathematical History Behind the Granger–Johansen Representation Theorem
Oxford Bulletin of Economics and Statistics, Volume 88, Issue 4, Page 587-602, August 2026.ABSTRACT When can a vector time series that is integrated once (i.e., becomes stationary after taking first differences) be described in error correction form? The answer to this is provided by the Granger–Johansen representation theorem. From a mathematical point of view, the theorem can be viewed as essentially a statement concerning the geometry of ...
Johannes M. Schumacher
wiley +1 more source
The norm of a truncated Toeplitz operator [PDF]
, 2010 We prove several lower bounds for the norm of a truncated Toeplitz operator and obtain a curious relationship between the H2 and H∞ norms of functions in model ...
Garcia, Stephan Ramon, Ross, William T.
core +4 more sources
Journal of Function Spaces, 2016 Let T1 be a generalized Calderón-Zygmund operator or ±I (the identity operator), let T2 and T4 be the linear operators, and let T3=±I. Denote the Toeplitz type operator by Tb=T1MbIαT2+T3IαMbT4, where Mbf=bf and Iα is the fractional integral operator.
Bijun Ren, Enbin Zhang
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Hyponormality of Toeplitz operators with non-harmonic symbols on the Bergman spaces
Journal of Inequalities and Applications, 2021 In this paper, we present some necessary and sufficient conditions for the hyponormality of Toeplitz operator T φ $T_{\varphi }$ on the Bergman space A 2 ( D ) $A^{2}(\mathbb{D})$ with non-harmonic symbols under certain assumptions.
Sumin Kim, Jongrak Lee
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Cointegration in a MIDAS Regression
Oxford Bulletin of Economics and Statistics, Volume 88, Issue 4, Page 712-725, August 2026.ABSTRACT Mixed data sampling (MIDAS) cointegration models are used to analyse variables observed at different frequencies. In this paper, we start from an assumed autoregressive distributed lag (ADL) model for high‐frequency observations, and derive the resulting representation when the dependent variable is only observed at a lower frequency.
H. Peter Boswijk, Philip Hans Franses
wiley +1 more source
Toeplitz Operators on the Weighted Bergman Space over the Two-Dimensional Unit Ball
Journal of Function Spaces, 2015 We extend the known results on commutative Banach algebras generated by Toeplitz operators with radial quasi-homogeneous symbols on the two-dimensional unit ball.
Alma García, Nikolai Vasilevski
doaj +1 more source