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.
88
votes
Why do roots of polynomials tend to have absolute value close to 1?
I think the following geometric argument is interesting and maybe sufficient to answer "why" at an intuitive level (?).
When we take the powers of $x$ in the complex plane, the absolute value scales g …
5
votes
concentration inequality for entropy from sample
Here's a step that seems nice enough to point out. It still leaves a parameter to pick, and I'm not sure it's ever better than applying Bernstein, but it does something different.
We can get a probab …
5
votes
1
answer
318
views
Bounding the max-loaded bin using${m \choose k} \|A\|_k^k$
Throw $m$ balls into $n$ bins independently, each ball selecting a bin from the distribution $A \in \Delta_n$. This question is about lower-bounding the max-loaded bin.
Background. In this MO answer I …
4
votes
3
answers
337
views
Do subgaussian variables obey the slightly-stronger-than-Chernoff tail bound?
If $X \sim Normal(0,1)$, then we have the tail bound:
$$ (*) \qquad\Pr[X > t] \leq \mathcal{O}\left(\frac{e^{-t^2/2}}{t}\right) .$$
Now for general variables $X$, a nice condition is that $X$ be su …
4
votes
Deciding when to stop searching for a new type of shell on a beach?
The Good-Turing estimator addresses a very similar problem.
The model is that there is an unknown number of types $n$ and a probability distribution $p \in \Delta_n$. Each time you pick up a new she …
4
votes
1
answer
472
views
Concentration inequalities in $\ell_{\infty}$ for sums of iid random ("nice") functions?
I'm looking for "tail-bound-like" inequalities that look like this (I state a specific setting but more general settings are interesting):
Let $D$ be a distribution on a set of "nice" functions $g …
4
votes
The relative error of approximating a binomial
Don't forget that far out in the left tail, the Binomial CDF is multiplicatively approximated by the PMF, because terms grow geometrically.
Example. For $t \leq \frac{np}{2}$, we claim $\Pr[X = t] \le …
4
votes
Accepted
Do these $L^p$ type statistics characterize distributions?
No, it looks like many different sufficiently symmetric distributions with enough concentration at $0$ will have $\arg\min_c E[|X-c|^p] = 0$ for all $p > 0$.
Concrete family of examples: if
$$ X = \be …
4
votes
Proofs of main probability results from other fields
Maybe this is a stretch, but laws of large numbers, and more precise concentration of measure bounds, can be proven by the "isoperimetric" approach which can be called geometric and was pioneered by T …
4
votes
The distribution of the number of chord intersections
For the expectation, linearity of expectation should help a lot. There are ${n\choose 2}$ pairs of chords, and if each chord is drawn i.i.d. then each pair has some probability of intersection of $p$, …
3
votes
Accepted
Does there exist a Penalized Conditional Expectation?
This is a bit different and doesn't address the question, but hopefully close enough to be useful: we know some things about $\mathbb{E} L(Z,Y)$ for other loss functions $L$.
If and only if $L$ is a …
3
votes
Example of a (strictly) proper scoring rule on a general measurable space?
Turns out that Gneiting and Raftery give an example in Section 4.2 of the continuous ranked probability score (CRPS), which is strictly proper for $\mathcal{P}$ equal to the Borel probability measures …
3
votes
Can we do better than Azuma-Hoeffding when the variance is small?
Adding to Iosif Pinelis' answer, there are two points here. First, as he says, the fact that we have a martingale rather than i.i.d. variables doesn't change much as proofs generally extend. So, secon …
3
votes
Accepted
Bounds on the mills ratio
Here's a sketch and a link for how I prove it. Let
$$ f(x) = - \left( \frac{1}{x} - \frac{1}{x^3} + \frac{3}{x^5}\right) \phi(x) .$$
Now show (lemma): $\frac{df}{dx} = \left(1 + \frac{15}{x^6}\righ …
3
votes
Finite-sample deviation bound of empirical distribution from true distribution
A self-contained proof.
Step 1: $\mathbb{E} \|\hat{P}_n - P\|_2^2 \leq \frac{1}{n}$.
Step 2: McDiarmid's inequality.
Let $X_i$ be the number of samples of $i \in \{1,\dots,k\}$. Then $X_i \sim \te …