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Undertherainbow
  • Member for 9 years, 10 months
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9 votes
2 answers
8k views

Definition of a convex cone

7 votes
1 answer
19k views

Standard Notation for diagonal matrices

3 votes
3 answers
229 views

Inequality involving a convex function

3 votes
2 answers
12k views

Find the area of the surface of revolution generated by revolving about the $x$-axis the hypocycloid $x=a\cos^3\theta$, $y=a\sin^3\theta$

3 votes
1 answer
1k views

General Position

3 votes
2 answers
366 views

Are the eigenvalues of a matrix and just its diagonal related?

2 votes
2 answers
96 views

What does $|$ mean?

2 votes
1 answer
5k views

Set of polynomials a subspace of P3?

2 votes
1 answer
1k views

The rank of a matrix of Gaussian random vectors

2 votes
0 answers
36 views

Rank of a matrix multiplied by random projections

2 votes
1 answer
2k views

Function with infinite maxima and minima [closed]

2 votes
1 answer
54 views

Integration of $|\text{cos}(t)|$

2 votes
2 answers
1k views

Sum of squared dot products of a unit vector with columns of an orthogonal matrix

2 votes
2 answers
203 views

Expected value of a function of a finite moment random variable [closed]

1 vote
2 answers
65 views

Definition of a function in terms of shifted deltas

1 vote
1 answer
392 views

What is the relationship between three points on a quadratic curve and the curves coefficients?

1 vote
0 answers
209 views

Differentiation with Matrix Coefficients and scalar variable.

1 vote
1 answer
332 views

Exact expression of variance of gaussian quadratic form

1 vote
2 answers
1k views

Is the inverse Fourier transform always defined?

1 vote
1 answer
268 views

Matrix in norm subscript notation [closed]

1 vote
0 answers
51 views

Degenerate random variable and joint Gaussianity with any Gaussian random variable

1 vote
1 answer
418 views

When is it equivalent to do a joint optimization over two variables in sequence over each variable?

0 votes
0 answers
136 views

Relation between spectral norm and entries of a matrix

0 votes
3 answers
73 views

Differentiating a scalar function $f := z \, \beta^T \left({\Sigma}+zI\right)^{-1} \beta$ w.r.t. $z$.

0 votes
1 answer
28 views

What does the expectation tell me about individual realizations (specifically in the Gaussian case)?

0 votes
1 answer
60 views

$||\textbf{A}\textbf{B}||_2=||\textbf{B}\textbf{A}||_2$?

0 votes
1 answer
18 views

Are the sets of outcomes of the underlying experiment mapped to specific values of a random variable necessarily disjoint?

0 votes
0 answers
50 views

Does any transformation of a random variable result in a valid PDF?

0 votes
1 answer
115 views

Conditions for $X$ and $Y$ independent of $Z$

0 votes
2 answers
137 views

Lower bound on a bilinear quadratic form