Results 51 to 60 of about 40,316 (199)
Conditions for Existence of Dual Certificates in Rank-One Semidefinite Problems [PDF]
, 2014 Several signal recovery tasks can be relaxed into semidefinite programs with rank-one minimizers. A common technique for proving these programs succeed is to construct a dual certificate.
Hand, Paul
core +1 more source
Canadian Journal of Statistics, EarlyView.Abstract Modern longitudinal data from wearable devices consist of biological signals at high‐frequency time points. Distributed statistical methods have emerged as a powerful tool to overcome the computational burden of estimation and inference with large data, but methodology for distributed functional regression remains limited.
Cole Manschot, Emily C. Hector
wiley +1 more source
Pick matrix conditions for sign-definite solutions of the algebraic Riccati equation [PDF]
, 2001 We study the existence of positive and negative semidefinite solutions of algebraic Riccati equations (ARE) corresponding to linear quadratic problems with an indefinite cost functional.
Rapisarda, Paolo, Trentelman, Harry L.
core +2 more sources
Communications on Pure and Applied Mathematics, EarlyView.Abstract We address the problem of regularity of solutions ui(t,x1,…,xN)$u^i(t, x^1, \ldots, x^N)$ to a family of semilinear parabolic systems of N$N$ equations, which describe closed‐loop equilibria of some N$N$‐player differential games with Lagrangian having quadratic behaviour in the velocity variable, running costs fi(x)$f^i(x)$ and final costs gi(
Marco Cirant, Davide Francesco Redaelli
wiley +1 more source
Support-based lower bounds for the positive semidefinite rank of a nonnegative matrix [PDF]
, 2013 The positive semidefinite rank of a nonnegative $(m\times n)$-matrix~$S$ is the minimum number~$q$ such that there exist positive semidefinite $(q\times q)$-matrices $A_1,\dots,A_m$, $B_1,\dots,B_n$ such that $S(k,\ell) = \mbox{tr}(A_k^* B_\ell)$.
Dirk, Oliver Theis, Troy Lee
core
A Unique "Nonnegative" Solution to an Underdetermined System: from Vectors to Matrices [PDF]
, 2009 This paper investigates the uniqueness of a nonnegative vector solution and the uniqueness of a positive semidefinite matrix solution to underdetermined linear systems.
Ao Tang +3 more
core +3 more sources
Uncertain Short‐Run Restrictions and Statistically Identified Structural Vector Autoregressions
Journal of Applied Econometrics, EarlyView.ABSTRACT This study proposes a combination of a statistical identification approach with potentially invalid short‐run zero restrictions. The estimator shrinks towards imposed restrictions and stops shrinkage when the data provide evidence against a restriction.
Sascha A. Keweloh, Shu Wang
wiley +1 more source
Heinz均值凸性的一个注记(A note on the convexity of the Heinz means)
Zhejiang Daxue xuebao. Lixue ban, 2013 Recently, KITTANEH obtained an improvement of the Heinz inequality for all unitarily invariant norms. In this note, we obtain a refinement of KITTANEH's result. We shall conclude this paper with some numerical examples.
ZOULi-min(邹黎敏)
doaj +1 more source
Metaplectic operators with quasi‐diagonal kernels
Mathematische Nachrichten, EarlyView.Abstract Metaplectic operators form a relevant class of operators appearing in different applications, in this work we study their Schwartz kernels. Namely, diagonality of a kernel is defined by imposing rapid off‐diagonal decay conditions, and quasi‐diagonality by imposing the same conditions on the smoothing of the kernel through convolution with the
Gianluca Giacchi, Luigi Rodino
wiley +1 more source
Robust constrained weighted least squares for in vivo human cardiac diffusion kurtosis imaging
Magnetic Resonance in Medicine, EarlyView.Abstract Purpose Cardiac diffusion tensor imaging (cDTI) can investigate the microstructure of heart tissue. At sufficiently high b‐values, additional information on microstructure can be observed, but the data require a representation such as diffusion kurtosis imaging (DKI).
Sam Coveney +6 more
wiley +1 more source