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ndrizza
  • Member for 8 years, 2 months
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6 votes
2 answers
1k views

Metric Tensor of Hyperboloid Model for Hyperbolic Space with Curvature $K$

6 votes
2 answers
4k views

Distribution of Dot-Product of Two Independent Multivariate Gaussian Vectors

5 votes
4 answers
164 views

Prove: $\operatorname{E}[X^2]<\infty\Longrightarrow \operatorname{E}[X]$ exists

5 votes
2 answers
3k views

Showing that mean of vectors minimizes the sum of the squared distances.

3 votes
1 answer
961 views

Computing $\lim_{n\to\infty}e^{-n}\sum_{k=0}^n \frac{n^k}{k!}$ with central limit theorem

3 votes
6 answers
665 views

Evaluating the integral $\int_{-\infty}^\infty x^2\frac{1}{\sqrt{2\pi}}e^{-\frac{1}{2}x^2} \ dx$

3 votes
0 answers
1k views

What is the distribution of the angle between two random vectors?

3 votes
1 answer
581 views

Projection of point onto closest point on geodesic in hyperbolic geometry (hyperboloid model)

3 votes
1 answer
72 views

Limit of Distance on Stereographically Projected Sphere for $K\to 0$

3 votes
0 answers
298 views

What is the Corresponding Operation of Möbius Addition for Spherical Geometries?

2 votes
1 answer
249 views

Volume of Ball on Spherical Manifold

2 votes
0 answers
95 views

Exponential Map of Stereographic Projection of Sphere (through North Pole)

2 votes
0 answers
54 views

Moment Matching Distributions

2 votes
1 answer
167 views

Projection from Poincaré Ball to Hyperboloid

2 votes
1 answer
99 views

Two approaches for determining the probability for the value of a random variable lead to different solutions

2 votes
1 answer
118 views

For invertible matrices $A$ and $C$, prove or disprove that $(C^{-1}BAB^T + I)$ is invertible.

2 votes
1 answer
288 views

For invertible $A$, $C$, prove that: $(A^{−1} + B^TC^{−1}B)^{−1}B^TC^{−1} = AB^T(BAB^T + C)^{−1}$

2 votes
0 answers
441 views

Meaning of best rank $k$ approximation of a matrix $A$

2 votes
1 answer
50 views

Correctness of proof for the convergence of a series

1 vote
1 answer
89 views

Integral: Area of figure described in polar coordinates

1 vote
1 answer
25 views

Exercise: Prove some properties about some numbers of a set.

1 vote
3 answers
7k views

Prove that $f(x,y)$ is continuous in $(0,0)$

1 vote
1 answer
124 views

Prove that $\sum_{n=1}^{\infty} (-1)^n\frac{n}{n+1}$ diverges

1 vote
1 answer
39 views

Prove or disprove: $\forall\rho,\sigma,\phi\subseteq A^2: \ \rho \subseteq \sigma \rightarrow \rho \circ \phi \subseteq \sigma \circ \phi$

1 vote
1 answer
854 views

Shortcuts for computing the eigenvalues of a linear transformation

1 vote
1 answer
370 views

Prove or disprove: $|\det(Q)|=1 \Longrightarrow Q$ is unitary.

1 vote
1 answer
61 views

Hash function to determine whether two vectors had an equal entry on some row

1 vote
1 answer
465 views

Derivation of why a diagonalizable matrix can be written as a sum of outer products $\Sigma=\sum_{i=1}^n \lambda_i v_i v_i^T$

1 vote
1 answer
498 views

Proof: Negative Binomial NB(n,p) is the sum of n iid random variables from Geom(p) by induction with convolution

1 vote
1 answer
59 views

Let $X_1,...,X_4\stackrel{iid}{\sim}\mathcal{N}(0,1)$, and $\overline{X}_4=\frac{1}{4}\sum_{i=1}^4 X_i$. What is $P[\overline{X}_4\geq-\frac{1}{2}]$?