Results 131 to 140 of about 564,115 (361)
ADMM Algorithmic Regularization Paths for Sparse and Large Scale Positive-Definite Covariance Matrix Estimation [PDF]
, 2022 Lin Xia, Guanpeng WANG, Xudong Huang
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, 2015 Given positive numbers p_1 < p_2 < ... < p_n, and a real number r let L_r be the n by n matrix with its (i,j) entry equal to (p_i^r-p_j^r)/(p_i-p_j). A well-known theorem of C. Loewner says that L_r is positive definite when 0 < r < 1.
Bhatia, Rajendra +2 more
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Predicting cervical cancer DNA methylation from genetic data using multivariate CMMP
Canadian Journal of Statistics, EarlyView.Abstract Epigenetic modifications link the environment to gene expression and play a crucial role in tumour development. DNA methylation, in particular, is gaining attention in cancer research, including cervical cancer, the focus of this study.
Hang Zhang +5 more
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Hidden Markov graphical models with state‐dependent generalized hyperbolic distributions
Canadian Journal of Statistics, EarlyView.Abstract In this article, we develop a novel hidden Markov graphical model to investigate time‐varying interconnectedness between different financial markets. To identify conditional correlation structures under varying market conditions and accommodate shape features embedded in financial time series, we rely upon the generalized hyperbolic family of ...
Beatrice Foroni +2 more
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Algorithm 298: Determination of the Square-Root of a Positive Definite Matrix [F1] [PDF]
, 1967 H. Späth
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Asymptotic independence in more than two dimensions and its implications on risk management
Canadian Journal of Statistics, EarlyView.Abstract In extreme value theory, the presence of asymptotic independence signifies that joint extreme events across multiple variables are unlikely. Although well understood in a bivariate context, the concept remains relatively unexplored when addressing the nuances of simultaneous occurrence of extremes in higher dimensions.
Bikramjit Das, Vicky Fasen‐Hartmann
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An algorithm for rescaling a matrix positive definite
Linear Algebra and its Applications, 1987 Given a square matrix M, find D diagonal, so that DM is positive definite, i.e. has its field of values in the right half plane. Here it is shown that this problem can be formulated as an infinite set of linear inequalities, and solved by solving a finite sequence of linear programming problems.
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Fluorescent Dyes for Probing Intracellular and Subcellular Polarity
Chemistry–Methods, EarlyView.Fluorescent probes are crucial tools for measuring cellular microenvironment polarity, a parameter that influences physiological organelle function and diseases such as cancer. This text details the probes' physicochemical principles, intracellular targeting strategies, and key photophysical parameters for polarity estimation.
M. Carmen Gonzalez‐Garcia +4 more
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On Positive Definite Solutions Of Quaternionic Matrix Equations
, 2010 The real representation of the quaternionic matrix is definited and studied. The relations between the positive (semi)define quaternionic matrix and its real representation matrix are presented. By means of the real representation, the relation between the positive (semi)definite solutions of quaternionic matrix equations and those of corresponding ...
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Degree theory for 4‐dimensional asymptotically conical gradient expanding solitons
Communications on Pure and Applied Mathematics, EarlyView.Abstract We develop a new degree theory for 4‐dimensional, asymptotically conical gradient expanding solitons. Our theory implies the existence of gradient expanding solitons that are asymptotic to any given cone over S3$S^3$ with non‐negative scalar curvature. We also obtain a similar existence result for cones whose link is diffeomorphic to S3/Γ$S^3/\
Richard H. Bamler, Eric Chen
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