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Eigenvalues of Hadamard product of two Wishart-type matrices

Given two independent Gaussian matrices with i.i.d. entries: $A\in\mathbb{R}^{n\times p}$ and $B\in\mathbb{R}^{n\times q}$, where and $A_{i,j},B_{i,j}\sim\mathcal{N}(0,1)$. Assume that $\max(p,q)<n....
M-Brust's user avatar
  • 31
3 votes
0 answers
116 views

Trace of Symmetric matrices in fixed rank

I am solving some problem related to symmetric matrices over a finite field $\mathbb{F}_q$ and I am stuck at the following problem: For every $a\in\mathbb{F}_q $, let $S_a(t,m)$ be the set of all $m\...
Singh's user avatar
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3 votes
0 answers
88 views

Statistical properties from the projection on Hadamard matrix

I am using Hadamard matrix to generate the measurement matrix in compressive sensing for signal acquisition. Consider all the rows except the first row, which consists of all 1's, as a candidate for ...
Amit's user avatar
  • 31
2 votes
1 answer
1k views

Components of a Gram matrix and its eigenvalues

The Gram Matrix is defined as $$\sum_{i=1}^n X_iX_i^T,$$ where $X_i$ is drawn from the unit sphere based according to some continuous distribution (Relation between eigenvalues and the gram matrix for ...
rostader's user avatar
  • 215
2 votes
0 answers
100 views

On a random matrix construction

Given a symmetric matrix $M\in\Bbb Z^{n\times n}$ or rank $r$ with absolute value of any entry bound by $2^{b^2-1}-1$ and maximum eigenvalue at most $\lambda$. We consider the set $\mathcal T_b$ of $\...
Turbo's user avatar
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2 votes
0 answers
279 views

Eigenvectors of convolution with a normal distribution over a restricted interval

Suppose I have a random variable $X_0$ with a p.d.f $f_0$ supported on the real interval $[a_0, b_0]$. $X_1$ is the restriction to $[a_1, b_1]$ of the sum $X_0 + g$, where $g$ is normally distributed $...
Arthur B's user avatar
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2 votes
0 answers
292 views

Seeking the normalizing constant (or any references) for a distribution over a subset of positive definite martrices

I'm interested in a probability distribution over the set of positive definite matrices with unit diagonal elements. That is, and $X$ such that: $X \in S^{n+}, \forall_{i}X_{ii} = 1$ where $S^{n+}$ ...
Jeremy 's user avatar
  • 379
2 votes
2 answers
215 views

How to analyze the value of convergence of functions of random matrices?

Consider a random i.i.d matrix $\mathbf{A}_{m\times n}$ with entries generated from a complex Gaussian distribution with zero mean and unit variance. I am interested in the large dimension analysis of ...
Math_Y's user avatar
  • 287
1 vote
0 answers
91 views

How to optimize parametric information-theoretic bounds?

I am faced with an information-theoretic upper bound, such as \begin{align} \sqrt{\alpha'}2^{I_\alpha(X;Y)}, \end{align} where $I_\alpha(X;Y)$ is the Rényi mutual information with parameter $\alpha>...
Math_Y's user avatar
  • 287
1 vote
0 answers
40 views

Asymptotic unitary invariance of rank-one spiked Gaussian matrix

I'm working on some Random Matrix Theory related stuff for my thesis, and i've come across the following problem: Consider a (normalized) spiked Wigner matrix $\mathbf{A}$ $$ \mathbf{A} = \frac{\beta}{...
Kawa's user avatar
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1 vote
0 answers
39 views

Constructing a centered distribution absolutely continuous with respect to uniform measure on the sphere with a pre-specified covariance?

Let $\mathcal{K}_n$ denote the space of $n \times n$, real symmetric positive semidefinite matrices $K$ having unit trace. It is easy to verify that for each $K \in \mathcal{K}_n$, there exists a ...
Drew Brady's user avatar
1 vote
0 answers
176 views

Maximum mutual information of random unitary transformation

Let $\mathbf{U}$ and $\mathbf{V}$ be random unitary matrices independent of random input vector $\mathbf{x}$. Moreover, $\mathbf{z}$ be random iid complex Gaussian vector with zero mean and identity ...
Math_Y's user avatar
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1 vote
0 answers
137 views

Choice of residual function for least squares error minimization

Good morning, I have the a set of data $(\sigma,D,\alpha_0)_i$, $i=1...n$ data. I want to determine two parameters $K_{IC}$, $C_f$ in the basic equation given as $K_{IC} = \sigma \sqrt{D} k_0(\...
gama's user avatar
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1 vote
0 answers
46 views

the 3th and 4th order statistics of Circularly Symmetric Complex Normal random vector?

Assume that ${\bf{z}} \in {\mathbb{C}}^{n \times 1}$ is a CSCG random vector denoted with $\mathcal{C} ~ (\bf{\mu} _0,\bf \Sigma _0)$ where $\mu _0$ and $\bf \Sigma _0$ are mean and contrivance matrix,...
user51780's user avatar
  • 275
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0 answers
31 views

What is the Fisher information matrix of the von Mises-Fisher distribution?

Assuming the von Mises-Fisher distribution as $$f_{p}(\mathbf{x}; \boldsymbol{\mu}, \kappa) = C_{p}(\kappa) \exp \left( {\kappa \boldsymbol{\mu}^\mathsf{T} \mathbf{x} } \right),$$ where $\kappa \ge 0$,...
Math_Y's user avatar
  • 287
0 votes
0 answers
92 views

Linear independence of Wishart matrices

Let $W\sim W_n(I,d)$ be a real Wishart matrix of an identity covariance matrix and $d$ degrees of freedom, i.e., $W=XX^T$ for $X$ being an $n\times d$ matrix whose entries are i.i.d sampled from a ...
user50394's user avatar
  • 123
0 votes
0 answers
132 views

Upper bound on the condition number of the product of a random sparse matrix and a semi-orthogonal matrix

Let $G \in \mathbb{R}^{n \times m}$ (m > n, m = O(n)) whose all entries are i.i.d. distributed as $\mathcal{N}(0, 1) * \text{Ber}(p)$. Let $V \in \mathbb{R}^{m \times n}$ be a fixed semi-orthogonal ...
nikhil_vyas's user avatar
0 votes
0 answers
93 views

Changing Couplings of Discrete Random Variables

Let $X,Y$ be two discrete random variables. Two joint mass distributions (couplings) with marginals $X$ and $Y$ and with entries $p_{i,j}=\mathbb{P}_1(X=i,Y=j)$ and $p_{i,j}'=\mathbb{P}_2({X=i,Y=j})$ ...
The Substitute's user avatar
-1 votes
1 answer
77 views

Variance of the logarithm of the mixed Rademacher and complex Gaussian distribution

Consider the scenario where $X$ is a Rademacher random variable taking values $\{−1,+1\}$ with equal probability, and $Z$ is a complex Gaussian random variable with a mean of $0$ and a variance of $\...
Math_Y's user avatar
  • 287
-1 votes
1 answer
60 views

Linear operator over a simplex space in a multinomial distribution parameter estimation problem

This is actually a variant of a well-known problem of how the parameters of a multinomial distribution can be estimated by maximum likelihood, and this arises from a final year project I undertook ...
Hephaes's user avatar