Search Results
Search type | Search syntax |
---|---|
Tags | [tag] |
Exact | "words here" |
Author |
user:1234 user:me (yours) |
Score |
score:3 (3+) score:0 (none) |
Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
Views | views:250 |
Code | code:"if (foo != bar)" |
Sections |
title:apples body:"apples oranges" |
URL | url:"*.example.com" |
Saves | in:saves |
Status |
closed:yes duplicate:no migrated:no wiki:no |
Types |
is:question is:answer |
Exclude |
-[tag] -apples |
For more details on advanced search visit our help page |
Theory and applications of probability and stochastic processes: e.g. central limit theorems, large deviations, stochastic differential equations, models from statistical mechanics, queuing theory.
1
vote
Accepted
Question on a random vector
For $1 \leq s' < s \leq n$ and $t,t' \in \mathbb{R}$, one has
$$
n(1-L_n) > t, (S(n)-1)(1-\frac{L_{S(n)-1}}{L_n}) > t',S(n)=s, Z(n) = s'
$$
precisely when
$$
U_1,\dots,U_{s'-1} < U_{s'},\\
U_{s'+1},\ …
2
votes
Accepted
Bounding function by random sampling
As pointed out by fedja, one can not expect the inequality yo hold with the same epsilon. However, the following holds : if $\mathbf{P}_{z}( |f(z)| \leq \epsilon ) \geq 1 - \delta$, with $\delta \ll n …
0
votes
One dimension random walk. Is hitting time Lipschitz with respect to target?
One should assume that $X$ is not a.s. $0$, in which case $\tau$ is a.s. integer-valued and non-constant, hence a.s. non-continuous, hence a.s. non-Lipschitz.
1
vote
Accepted
Product of estimates of mean values - Concentration of measure inequality
The simplest idea is to estimate the variance. One has
$$
\left(\prod^{d}_{j=1}\hat{\mu}_{j} \right)^2=\frac{1}{n^{2d}}\sum^{n}_{i_1,...,i_{2d}=1}\prod^{d}_{j=1}x^{(i_j)}_j x^{(i_{j+d})}_j
$$
When $i_ …
10
votes
Accepted
Random walk to stay in an interval forever
Yes. Indeed, if $s = \sum_{i \geq 1} t_i^2 <1$, then
$$
\mathbb{P}[ \ \ \forall n, \sum_{i=1}^n X_i \in [-1,1] \ \ ] \geq 1-s > 0.
$$
To see this, note that $M_n = |\sum_{i=1}^n X_i|$ is a nonnegativ …
10
votes
Accepted
Current state of the Komlos conjecture on vector balancing
For fixed $d$, one can actually achieve a bound independent of $n$. More precisely, $K=K(d)=O(\sqrt{d})$ is fine, uniformly in $n$.
Proof : the unit ball of $\mathbb{R}^d$ can be covered by $2C^d$ ba …