Absolute convex hull of rank 1-correlation matrices? The 2019 Stack Overflow Developer Survey...
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Absolute convex hull of rank 1-correlation matrices?
The 2019 Stack Overflow Developer Survey Results Are InConvex hull of orthogonal matricesConic hull of outer productsRank of orthogonal projection to prep of null-space, right-singular matrix and identity matrixName of “reverse convex hull”Convex hull of the set of stable matrices?Bounds on gap between least eigenvalues of correlation matrix and its principal minorsIs there any relation between weights in the eigenvector (corresponding to least eigenvalue) and the columns of a correlation matrix?Why is Sklansky algorithm convex hull wrongConvex hull spanning n-percent of pointsConvex hull of {-1, 1} rank-1 matrices?
$begingroup$
Does there exist a ''universal'' constant, $c > 0$ say, such that for any(!) $k in mathbb{N}$ every(!) $k times k$-correlation matrix $Sigma$ can be written as $Sigma = cTheta$, where $Theta$ is an element of the absolute convex hull of $k times k$-correlation matrices of $underline{rank hspace{0.1cm} 1}$?
I guess there exists a counterexample. However, I haven't found one so far. Any hints and links to suitable references are highly welcome!
linear-algebra statistics matrix-rank positive-semidefinite convex-hulls
asked Mar 22 at 0:01
arcsinarcsin
12
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add a comment |
$begingroup$
Does there exist a ''universal'' constant, $c > 0$ say, such that for any(!) $k in mathbb{N}$ every(!) $k times k$-correlation matrix $Sigma$ can be written as $Sigma = cTheta$, where $Theta$ is an element of the absolute convex hull of $k times k$-correlation matrices of $underline{rank hspace{0.1cm} 1}$?
I guess there exists a counterexample. However, I haven't found one so far. Any hints and links to suitable references are highly welcome!
linear-algebra statistics matrix-rank positive-semidefinite convex-hulls
asked Mar 22 at 0:01
arcsinarcsin
12
$endgroup$
add a comment |
$begingroup$
Does there exist a ''universal'' constant, $c > 0$ say, such that for any(!) $k in mathbb{N}$ every(!) $k times k$-correlation matrix $Sigma$ can be written as $Sigma = cTheta$, where $Theta$ is an element of the absolute convex hull of $k times k$-correlation matrices of $underline{rank hspace{0.1cm} 1}$?
I guess there exists a counterexample. However, I haven't found one so far. Any hints and links to suitable references are highly welcome!
linear-algebra statistics matrix-rank positive-semidefinite convex-hulls
asked Mar 22 at 0:01
arcsinarcsin
12
$endgroup$
Does there exist a ''universal'' constant, $c > 0$ say, such that for any(!) $k in mathbb{N}$ every(!) $k times k$-correlation matrix $Sigma$ can be written as $Sigma = cTheta$, where $Theta$ is an element of the absolute convex hull of $k times k$-correlation matrices of $underline{rank hspace{0.1cm} 1}$?
I guess there exists a counterexample. However, I haven't found one so far. Any hints and links to suitable references are highly welcome!
linear-algebra statistics matrix-rank positive-semidefinite convex-hulls
linear-algebra statistics matrix-rank positive-semidefinite convex-hulls
asked Mar 22 at 0:01
arcsinarcsin
12
asked Mar 22 at 0:01
arcsinarcsin
12
asked Mar 22 at 0:01
arcsinarcsin
12
asked Mar 22 at 0:01
arcsinarcsin
12
asked Mar 22 at 0:01
arcsinarcsin
12
12
add a comment |
add a comment |
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