Skip to main content
davcha's user avatar
davcha's user avatar
davcha's user avatar
davcha
  • Member for 9 years, 9 months
  • Last seen more than 1 year ago
13 votes
1 answer
2k views

Rank, nuclear and Frobenius norms of a matrix

8 votes
1 answer
3k views

Commute time distance in a graph

3 votes
1 answer
116 views

Maximize $\gamma$ such that $A+\gamma B\succeq 0$

3 votes
3 answers
1k views

How to prove $\left(\sum_{i=1}^n x_i\right)^2 \le n\sum_{i=1}^n x_i^2$? [duplicate]

3 votes
2 answers
237 views

Undecidability and truth

2 votes
1 answer
641 views

Why is the duality gap zero for non convex quadratic programming with a single constraint?

2 votes
0 answers
92 views

Expected number of trials ; probability increases after each failure

1 vote
1 answer
23 views

If $f(x)^2$ is convex and $f(x)>1$, does $\arg\min_x f(x)^2=\arg\min_x f(x)$?

1 vote
0 answers
69 views

Probability of having at least one table with $n$ customers

1 vote
1 answer
61 views

Inverse of $I+MW$

1 vote
0 answers
106 views

Balancing a game, or proving the imbalance of a game

1 vote
1 answer
134 views

Second derivative of $\sum_i \left(\frac{1}{1+\|Xa_i\|^2}-b_i\right)^2$

1 vote
0 answers
42 views

Maximize $\gamma$ such that $A+\lambda B-\gamma C\succeq 0$

1 vote
1 answer
82 views

How can I show that $(a^\top \otimes b)(b^\top \otimes a) = (a \otimes b)(b \otimes a)^\top$?

1 vote
2 answers
124 views

Optimizing a problem using Lagrange multipliers

1 vote
1 answer
82 views

Minimum of a convex function w.r.t. a subset of its domain

0 votes
0 answers
34 views

Convexity of a function with discrete parameters

0 votes
0 answers
40 views

Probability of an event occuring $n$ times, given that it can occur $n$ times or does not occur at all.

0 votes
1 answer
171 views

Why this matrix is not a distance matrix?

0 votes
1 answer
202 views

What Laplacian should we use for spectral clustering?

0 votes
0 answers
53 views

A paradox with probabilities

0 votes
2 answers
696 views

Partial derivative of the trace of matrix entry-wise exponential?

0 votes
1 answer
253 views

Gradient of a matrix-matrix function

0 votes
1 answer
78 views

If $m \ge 8 s \log(m^2 s)$, how much greater $m$ is relatively to $s$?

0 votes
1 answer
700 views

Unique minimizer of $\|x\|_{\mathcal A}$ subject to $\Phi x=\Phi x_0$

0 votes
2 answers
59 views

Show that $\frac{1}{2}\frac{d}{d\Psi} \left(\frac{d\Psi}{dx}\right)^2=\frac{d^2\Psi}{dx^2}$ [closed]

0 votes
0 answers
21 views

Distribution of a sequence obtained from a simple stochastic process