Results 11 to 20 of about 6,523,303 (221)
The Totally Positive Completion Problem: The 3-by-n Case
Special Matrices, 2021 The 3-by-n TP-completable patterns are characterized by identifying the minimal obstructions up to natural symmetries. They are finite in number.
Carter D. +4 more
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Doubly constrained totally positive line insertion
Special Matrices, 2020 It is shown that in any TP matrix, a line (row or column) with two speci˝ed entries in any positions (and the others appropriately chosen) may be inserted in any position, as long as the two entries are consistent with total positivity.
Johnson Charles R., Allen David W.
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Coherence Matrix Estimation With Total Positivity Regularization for Interferometric Phase Linking
IEEE Journal of Selected Topics in Applied Earth Observations and Remote SensingInterferometric phase linking has become a critical step in distributed scatterer interferometry, yet its performance is significantly affected by inaccuracies in the coherence matrix and its inverse, such as the precision matrix.
Changjun Zhao, Yan Yan, Hanwen Yu
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AxiomsThe approach to solving linear systems with structured matrices by means of the bidiagonal factorization of the inverse of the coefficient matrix is first considered in this review article, the starting point being the classical Björck–Pereyra algorithms
José-Javier Martínez
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Covariance Matrix Estimation under Total Positivity for Portfolio Selection [PDF]
Journal of Financial Econometrics, 2020 Abstract Selecting the optimal Markowitz portfolio depends on estimating the covariance matrix of the returns of N assets from T periods of historical data. Problematically, N is typically of the same order as T, which makes the sample covariance matrix estimator perform poorly, both empirically and theoretically.
Agrawal, Raj, Roy, Uma, Uhler, Caroline
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The development and evaluation of psychometric properties of the Economic-Psychological Resilience Scale (EPRS) [PDF]
پژوهشهای علوم شناختی و رفتاری, 2022 The present study aimed to develop the Economic-Psychological Resilience Scale (EPRS) and evaluate its psychometric properties. To this end, a descriptive research method was used.
Somayeh Pourehsan +1 more
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Progressive Iterative Approximation with Preconditioners
Mathematics, 2020 The progressive iterative approximation (PIA) plays an important role in curve and surface fitting. By using the diagonally compensated reduction of the collocation matrix, we propose the preconditioned progressive iterative approximation (PPIA) to ...
Chengzhi Liu, Zhongyun Liu
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Totally positive matrices and totally positive hypergraphs [PDF]
, 2001 A real matrix is totally positive if all its minors are nonnegative. In this paper, we characterize 0–1 matrices that can be transformed into totally positive matrices by permutations of rows and ...
Lehel, Jenő +2 more
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EXCLI Journal : Experimental and Clinical Sciences, 2022 Cell-based therapy and tissue engineering are promising substitutes for liver transplantation to cure end-stage liver disorders. However, the limited sources for healthy and functional cells and poor engraftment rate are main challenges to the cell-based
Mostafa Najar-Asl +9 more
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Total positivity of a shuffle matrix [PDF]
Involve, a Journal of Mathematics, 2012 Holte introduced a [math] matrix [math] as a transition matrix related to the carries obtained when summing [math] numbers base [math] . Since then Diaconis and Fulman have further studied this matrix proving it to also be a transition matrix related to the process of [math] -riffle shuffling [math] cards.
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