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1 vote
0 answers
27 views

Centered Subgaussian Variables have better Properties

I am trying to understand the following proof: Main Confusion: In particular, I am having a very hard time understanding the chain of inequalities in the proof for (3)': I think the first equality is ...
Partial T's user avatar
  • 593
0 votes
1 answer
17 views

Understanding the proof for Properties of Subgaussian Variables

Here are the definitions, statements and the proof that I am stuck on: I am stuck on the last part of the proof where the author claims that setting $C = e$ automatically guaranties that (1) holds ...
Partial T's user avatar
  • 593
1 vote
0 answers
23 views

Confusion about LLN for Empirical Processes/Measures

I have seen the following LLN result on empirical measures: (Statement 1) Let $X, X_1, X_2, \cdots, X_n$ be i.i.d. random variables taking values in $[0, 1]$. Then $$ \mathbb{E}\sup_{f \in \mathcal{F}...
Partial T's user avatar
  • 593
0 votes
0 answers
42 views

Why is Bernstein's Inequality legal here?

This is a follow up question based on this post: Bounding rows of random matrices. I can not see why we can use Bernstein's inequality as mentioned in the answer. In particular, it seems like the ...
Partial T's user avatar
  • 593
0 votes
1 answer
68 views

Probabilistic Combinatorial problem - consecutive runs of $1$s in a string of $0$s and $1$s

Let $n$ values $0$ or $1$ be arranged around a circle, and for a given $k$ consider the number of runs of $k$ consecutive $1$s. Suppose the $n$ values are independent and each of them is equal to $1$ ...
user avatar
0 votes
0 answers
25 views

Need Help Understanding the Proof of Lower Bound on Expectation of Maximum Gaussians

I am trying to follow the proof given here: http://www.gautamkamath.com/writings/gaussian_max.pdf. In particular, I would like to understand the following crude bound mentioned in the paper: My ...
Partial T's user avatar
  • 593
0 votes
1 answer
76 views

Debug a flawed solution to a problem on independence and orthogonality

From Exercise $24$ in Tao's note: https://terrytao.wordpress.com/2015/10/12/275a-notes-2-product-measures-and-independence/comment-page-2/#comment-682699 Let ${X}$ be a random variable taking values ...
shark's user avatar
  • 1,011
0 votes
0 answers
29 views

Sub-Gaussian Norm Basic Property: Infimum is Minimum?

This is the definition of a sub-gassian norm of a random variable $X$: $$ \| X \|_{\Psi_2} = \inf\{ t > 0: \mathbb{E}\exp(X^2/t^2) \leq 2 \}. $$ It is claimed that we have: $$ \mathbb{E}\exp(X^2/\| ...
Partial T's user avatar
  • 593
0 votes
1 answer
74 views

Question about Minkowski dimension

I'm learning Minkowski and Hausdorff dimensions to study Brownian motion right now, and I'm trying to understand the reasoning behind the Minkowski dimension of the set $(0,1,1/2, 1/3,\ldots)$ being $...
EzBots's user avatar
  • 303
1 vote
1 answer
37 views

The Countable Collection of Measures on a Given Measurable Space Is a Convex Cone

I am proving the following statement: Given any countable collection $\{\mu_{n}\}_{n=1}^{\infty}$ of measures on a measurable space $(\Omega,\mathcal{F})$, the summation $\mu:=\sum_{n=1}^{\infty}c_{n}...
JacobsonRadical's user avatar
0 votes
0 answers
145 views

Prove that the Lebesgue function is continuous

I am self-learning probability theory from the text Measure, Integral and Probability, by Capinski and Kopp. Exercise problem 2.3 asks to investigate the Cantor-Lebesgue function, show that it is ...
Quasar's user avatar
  • 5,450
1 vote
0 answers
57 views

How they are shifting cover to non-cover space?

I was reading this paper. I am unable to understand the blocked step. Can anybody help me understanding that step? Proof of Theorem 4. Define $\mathcal{W}_L \subseteq \mathcal{W}$ by $$ \mathcal{W}_L \...
Turing's user avatar
  • 456
0 votes
0 answers
46 views

An unusual proof of the image measure theorem

This is Theorem 4.10, p. 101, of Probability Theory: A Comprehensive Course, by Klenke. I have written an unusual proof which I think/hope is correct, and I'm wondering if anyone has any comments on ...
Novice's user avatar
  • 4,252
1 vote
0 answers
381 views

Proving Conditional Cauchy Schwartz inequality.

currently I try to solve the following exercise $8.2.6$ in Klenke Probability Theory for fun. It states the following: Let $X,Y \in L^2(P)$ be random variables on $(\Omega,F,P)$ then prove the ...
a.s. graduate student's user avatar
2 votes
0 answers
45 views

A property of measure-generating function

I'm reading about measure-generating function (page 28) in Analysis III by Amann/Escher Let $F: \mathbb{R} \rightarrow \mathbb{R}$ be increasing and continuous from the left. We say that $F$ is a ...
Akira's user avatar
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