Skip to main content

All Questions

Filter by
Sorted by
Tagged with
4 votes
0 answers
142 views

Algebraic area of Brownian half-plane excursion

Is anything known about the distribution of the algebraic area, à la Lévy's stochastic area, of a Brownian excursion in the half-plane? To be precise, letting $x>0$, we consider the path $(X_t,Y_t)...
Timothy Budd's user avatar
  • 3,927
0 votes
0 answers
43 views

For a convex body $K\subset R^n$, does the quantity $\min_{t>0} E[t^{-1} \|tg - \pi_K( t g)\|_2]$ have a name? Where has it been studied?

Consider a convex compact set $K\subset R^n$ (with non-empty interior if that helps). Let $\Pi_K:R^n\to K$ be the projection onto $K$, defined as $$ \Pi_K(x) = \operatorname{argmin}_{k\in K} \|k-x\| $$...
jlewk's user avatar
  • 1,724
0 votes
0 answers
77 views

Texts on coalescent theory/probability methods for DNA evolution

I am starting a PhD on mitochondrial evolution modelling with a focus on probabilistic methods and coalescent theory. For this purpose, I am looking for advanced textbooks on probability methods for ...
Enforce's user avatar
  • 203
1 vote
1 answer
99 views

Asymptotic variance for averages of trajectory functionals of Markov chain

I am looking for references on theory for convergence rates of ergodic averages of a Markov chain in the more general setting where the functional is over multiple states or even a whole trajectory, ...
itchidese's user avatar
10 votes
2 answers
828 views

On martingale convergence

Let $(X_t)_{t\ge0}$ be a martingale with continuous paths. It was previously shown here and here that then it is impossible that $X_t\to\infty$ almost surely as $t\to\infty$. Is it possible that there ...
Iosif Pinelis's user avatar
4 votes
1 answer
311 views

Examples of Borel probability measures on the Schwartz function space?

Let $\mathcal{S}(\mathbb{R}^d)$ be the Frechet space of Schwartz functions on $\mathbb{R}^n$. Its dual space $\mathcal{S}'(\mathbb{R}^d)$ is the space of tempered distributions. Minlos Theorem as ...
Isaac's user avatar
  • 3,477
1 vote
0 answers
90 views

What do $\gamma$-radonifying operators radonify?

In the second volume of their Analysis in Banach Spaces, Hytönen et al. introduce the notion of $\gamma$-radonifying operator more or less as follow. Let $(\gamma_j)_{j\in\mathbf N}$ be a sequence of ...
P. P. Tuong's user avatar
1 vote
1 answer
314 views

Proof of the Dunford-Pettis theorem in the context of probability spaces

I'd like to know if there's a proof of the Dunford-Pettis theorem without using relatively advanced theorems of functional analysis such as Eberlein–Smulian Theorem. Since I'm only interested in ...
rfloc's user avatar
  • 627
5 votes
0 answers
184 views

Question about $n$ random points in a regular polygon, and a limiting probability

Suppose we choose $n$ uniformly random points in a disk, then draw the smallest circle that encloses all of those points. There is evidence suggesting that the probability that the enclosing circle is ...
Dan's user avatar
  • 3,527
1 vote
2 answers
262 views

Is the Boltzmann entropy lower semi-continuous in the weak topology induced by $C_b (\mathbb R^d)$?

For Lebesgue-absolutely continuous probability measures $\rho\ll \mathcal{L}^d$ in the whole space $\mathbb{R}^d$ with finite second moments (i-e $\rho\in \mathcal{P}^2_{ac}(\mathbb{R}^d)$), let $$ \...
Akira's user avatar
  • 835
4 votes
2 answers
255 views

Are the sublevel sets of Boltzmann entropy compact in Wasserstein distance?

For Lebesgue-absolutely continuous probability measures $\rho\ll \mathcal{L}^d$ in the whole space $\mathbb{R}^d$ with finite second moments (i-e $\rho\in \mathcal{P}^2_{ac}(\mathbb{R}^d)$), let $$ \...
Akira's user avatar
  • 835
3 votes
1 answer
220 views

Conditional expectation as square-loss minimizer over continuous functions

It is well-known that the conditional expectation of a square-integrable random variable $Y$ given another (real) random variable $X$ can be obtained by minimizing the mean square loss between $Y$ and ...
fsp-b's user avatar
  • 463
3 votes
1 answer
561 views

On the convergence in total variation

$\newcommand\R{\mathbb R}$For a probability measure $\mu$ over $\R^2$ and a unit vector $u\in\R^2$, let $\mu^u$ denote the pushforward of $\mu$ under the projection map $\R^2\ni x\mapsto u\cdot x\in\R$...
Iosif Pinelis's user avatar
7 votes
0 answers
222 views

Projected polar chessboard measure convergence in total variation?

$\newcommand\R{\mathbb R}\newcommand\C{\mathbb C}\newcommand\ga{\gamma}$For natural $n$, let $E_n$ be the set of all points in $\R^2$ with "polar coordinates" $(r,t)$ in the set $$F_n:=\...
Iosif Pinelis's user avatar
0 votes
0 answers
55 views

Modeling player interactions in multi-dimensional rating systems

In traditional rating systems (such as Elo), a player's strength is represented by a single scalar value, which is assumed to be consistent across different opponents. However, in some games, the ...
mb1's user avatar
  • 1
2 votes
1 answer
133 views

Can convergence in distribution necessarily be realised by almost-sure convergence?

Let $X$ be a Polish space. Let $(\mu_n)_{n \in \mathbb{N} \cup \{\infty\}}$ be a family of Borel probability measures $\mu_n$ on $X$ such that $\mu_n \to \mu_\infty$ weakly as $n \to \infty$. For each ...
Julian Newman's user avatar
1 vote
0 answers
134 views

Generating realizations from $n$-dimensional geometric Brownian motion where the variables are constrained to sum to 1

Is there a way to simulate an $N$-dimensional geometric Brownian motion i.e. variable $$x_i, i \in [1, N] $$ is diffusing in log-space such that $$\log (x_i)$$ follows a Brownian motion with a given ...
arrhhh's user avatar
  • 21
9 votes
2 answers
496 views

Is there a determinantal point process proof of the Keating-Snaith formula for the cumulants of the log characteristic polynomial of a random matrix?

For $U$ a unitary $N \times N$ matrix, randomly distributed according to Haar measure, we have the complex-valued random variable $\log (\det (1-U))$. The real part and imaginary parts of $\log (\det (...
Will Sawin's user avatar
  • 148k
0 votes
1 answer
74 views

Distribution of an unordered set of random variables

Suppose we have a set of deterministic points $y_{1}, \dots, y_{m} \in \mathbb{R}^{n}$. Let $(\Omega, \mathcal{F}, \mathbb{P})$ be a probability space and let $T : \mathbb{R}^{n} \times \Omega \to \...
user13243542345452's user avatar
1 vote
0 answers
168 views

Optimal transport-like problem where the objective depends on conditional probability distribution

$\DeclareMathOperator\marg{marg}$I would like to know if the following problem can be studied as an optimal transport problem, possibly imposing additional assumptions on the data. Consider two sets $\...
Francesco Bilotta's user avatar
0 votes
0 answers
161 views

Markov process with time varying transition kernels

I cross post this question from StackExchange as it may be more appropriate. I am interested in studying the evolution of a variable $\alpha_t\in [0,1]$ governed by the following stochastic dynamical ...
Francesco Bilotta's user avatar
0 votes
0 answers
87 views

coupling method for first hitting times

Consider a Markov process $(X_t: S \to S)_{t \ge 0}$ that begins with two initial probabilities $\mu_1$ and $\mu_2$ defined on the state space $S$. Let's define the first hitting time $\tau$ as $\tau:=...
user avatar
2 votes
2 answers
167 views

Example of random walk in a random environment (RWRE) saying things on the environment

I was wondering if anyone is aware of works/articles/examples where random walks in a random environment (RWRE) are actually used for obtaining information on the random environment. To clarify a bit, ...
Cal's user avatar
  • 59
2 votes
0 answers
70 views

Reference request : A SPDE model

Let $\Omega_0\subset\mathbb R^d$ be open and bounded with sufficiently smooth boundary $\partial\Omega_0$. Let $O\subset \Omega_0$ be a random open subset. Set $\Omega:=\Omega_0\setminus O$. Consider ...
Fawen90's user avatar
  • 1,399
9 votes
1 answer
735 views

Where has this structure been observed?

$\newcommand{\M}{\mathcal{M}}$Let $M$ be a monoid. Consider the following structure: $R_X,R_Y:\mathbb{Z}^2 \to M$ satisfying the following "compatiblity-relation": $$R_X (x, y) \cdot R_Y (x +...
Asaf Shachar's user avatar
  • 6,741
1 vote
0 answers
87 views

Symmetry of the isoperimetric profile

Given a probability measure $\mu$ on a metric space $(X, \mathsf{d})$, the $(\mu-)$Minkowski content of a set $A$ is defined as $$\mu^+ (A) := {\lim\inf}_{r \to 0^+} \frac{\mu ( A_r \setminus A)}{r},$$...
πr8's user avatar
  • 801
1 vote
0 answers
91 views

Large deviation inequalities for number of coupon types collected by a coupon collector with fixed budget

In the generalized Coupon Collector's Problem, there are $N$ types of coupon, and for any $i \in [N] := \{1,2,\ldots,N\}$, $p_i \ge 0$ is the probability of obtaining a type-i coupon on any trial. ...
dohmatob's user avatar
  • 6,853
1 vote
0 answers
143 views

Estimator for the conditional expectation operator with convergence rate in operator norm

Let $X$ and $Z$ be two random variables defined on the same probability space, taking values in euclidian spaces $E_X$ and $E_Z$, with distributions $\pi$ and $\nu$, respectively. Let $L^2(\pi)$ ...
Caio Lins's user avatar
  • 111
3 votes
2 answers
102 views

Reference for Wiener type measure on $C(T)$ when $T$ is open

I'm considering Gaussian process on open domain $T$ in $\mathbb{R}^n$ and I tried to follow the abstract Wiener space construction of Gross. Since my sample paths are meant to be continuous, I thought ...
Kiyoon Eum's user avatar
0 votes
0 answers
71 views

References on estimates for suprema of uncentered Gaussian processes?

Let $X_t, t \in T$ denote a centered Gaussian process. Let $d(t, s) = \sqrt{\mathbb{E} (X_t - X_s)^2}$. Consider a mean function $t \mapsto \mu_t$. Define the expected supremum $$ S(T, \mu) = \mathbb{...
Drew Brady's user avatar
2 votes
1 answer
266 views

Ergodicity of linear dynamical systems and convergence of covariance matrices

Let $z(n+1)=Bz(n)+\xi(n+1)$ be an $N$-dimensional linear dynamical system with $\left(\xi(n)\right)_{n\in\mathbb{N}}$ being i.i.d. with $\xi(n)\sim\mathcal{N}(0,\Sigma_{\xi})$. Assumptions: a) The ...
Augusto Santos's user avatar
5 votes
1 answer
400 views

Lower tail of random rank one sums?

Let $\{x_i\}_{i\geq 1}$ be iid random elements of the sequence space $\ell^2(\mathbb{N})$; assume that $\|x_i\|_2 \leq 1$ almost surely. Let $\Sigma = \mathbb{E}[x_1 \otimes x_1]$. Define $$ \Sigma_n =...
Drew Brady's user avatar
3 votes
1 answer
407 views

Relative entropy equality for a sequence of Bernoulli random variables

We are given two joint probability distributions, $p$ and $q$, of $n$ Bernoulli random variables $X_1, X_2, \ldots, X_n$. We denote by $p(x_k\mid x^{k-1})$ the probability $\mathbb{P}_p(X_k=x_k\mid ...
Penelope Benenati's user avatar
0 votes
0 answers
52 views

Classifier-specific lower bounds on the misclassification rate in binary classification

Consider a binary classification problem for $(X,Y)$, and let $\hat{f}$ be a proposed classifier. We wish to bound the misclassification rate $P(\hat{f}(X)\ne Y)$. There are many known lower bounds on ...
tim523's user avatar
  • 13
2 votes
0 answers
269 views

Singular values of Kronecker product of random matrices

I'm looking for a way to evaluate $\mathbb{E} \| (\mathbf{X} \mathbf{Q})^+ \|$ for a random matrix $\mathbf{X} \in \mathbb{R}^{r \times n}$ and a (fixed) matrix $\mathbf{Q} \in \mathbb{R}^{n \times \...
Uria Mor's user avatar
  • 121
1 vote
2 answers
355 views

Reference request and clarification for Central Limit Theorem for complex random variables

I'm looking for a reference and a proof of the following version (or eventually a more general version) of the Central Limit Theorem for complex random variables. Theorem. Let $Z_1, Z_2, \dots, Z_n$ ...
rosan98's user avatar
  • 361
2 votes
0 answers
127 views

Measure algebra for a family of probability measures

Let $(X,B,P)$ be a probability space, $I_P$ the $\sigma$-ideal of $P$-null sets and \begin{align} B_P = B \ltimes I_P &= \{ A \mathbin{\triangle} N \mid A \in B, N \in I_P \} \end{align} the ...
Packo's user avatar
  • 285
0 votes
0 answers
112 views

Additivity of purity of random matrix products

Suppose $M$ is an $n\times n$ matrix with IID random entries drawn from $\mathcal{D}$ and $\sigma$ is the vector of its singular values. Define purity of $M$ as $$\rho(M)=\frac{n \sum_i \sigma_i^4}{\...
Yaroslav Bulatov's user avatar
20 votes
1 answer
2k views

Roadmap to Ergodic Theory

I have recently been interested in going deeper into ergodic theory, beyond an introductory level of knowledge. Background wise, my training has mostly been in stochastic analysis, and I have a ...
Nate River's user avatar
  • 6,195
4 votes
1 answer
197 views

On a double sum involving binomial coefficients

For natural $n$, let \begin{equation} p_n:=2^{1-n}\sum_{v=1}^l \binom l{(v+l)/2}1(v\equiv l) \sum_{u=1-v}^{v-1}\binom k{(u+k)/2}1(u\equiv k), \tag{1}\label{1} \end{equation} where $k:=\lfloor(n+1)/...
Iosif Pinelis's user avatar
0 votes
0 answers
49 views

Gaussian white noise model in application

I am interested in applications (to data) of non-parametric statistics, and my question concerned the Gaussian white noise model defined by, $$ X_{t_1, \ldots, t_d}=f\left(t_1, \ldots, t_d\right) d ...
BabaUtah's user avatar
8 votes
1 answer
323 views

On a matrix inequality

$\newcommand{\R}{\mathbb R}\newcommand{\tr}{\operatorname{tr}}$It follows from Proposition 7 and this recent answer that, for any positive-definite $n\times n$ symmetric real matrices $A$ and $B$, $$\...
Iosif Pinelis's user avatar
1 vote
0 answers
68 views

Limiting value of expectation of $\operatorname{tr}(BR(z))$, where $R(z) := (X^\top X - z I_d)^{-1}$ and $X \sim N_{n,d}(0,A)$

Let $A=A(d)$, and $B=B(d)$ be (sequences of) deterministic positive-definite $d \times d$ matrices and let $X$ be an $n \times d$ random matrix with iid rows from $N(0,A)$. Let $R$ be the resolvent of ...
dohmatob's user avatar
  • 6,853
2 votes
0 answers
313 views

Correlation decay rate

Let $T$ be a continuous transformation of a probability measure space $(X,\mathcal{B}(X),\mu)$ and $\varphi ,\phi \in L^2(\mu)$ (so-called observable) . The correlation function of $\varphi ,\phi$ (a ...
Mrcrg's user avatar
  • 136
1 vote
1 answer
96 views

Asymptotic behavior of a Markov process on the set of $\{0,1\}$-polynomials

This question is cross-posted from https://math.stackexchange.com/questions/4711799/asymptotic-behavior-of-a-markov-process-on-the-set-of-0-1-polynomials I am trying to study the asymptotic behavior ...
Francesco Bilotta's user avatar
6 votes
1 answer
379 views

Probability that the ratio of products of randomly chosen natural numbers is unbounded

Let $N$ be a finite subset of $\mathbb{N}$, where $|N|>1$. For $i\in\mathbb{N}$, let $a_i$ and $b_i$ be chosen uniformly at random from $N$. Is it true that $\mathbb{P}[\sup_{n\in\mathbb{N}}\{\frac{...
Alice Kerr's user avatar
2 votes
1 answer
248 views

Connected components in random regular graphs

Suppose we take a random regular graph $G_{2n, r}$, where $n$ is large. Let us also assume that $r$ is fixed, (not dependent on $n$). Let's say that half of the vertices of the graph are colored black ...
SMS's user avatar
  • 1,407
9 votes
1 answer
1k views

The length of the longest consecutive string of heads or tails that occur asymptotically almost surely when a unbiased coin is flipped repeatedly

Consider an unbiased coin being flipped $n$ times, and suppose we label the outcomes as Heads = 0, and Tails = 1. Then the result of the flipping is a finite binary sequence of length $n$. Let us ...
positron's user avatar
-1 votes
2 answers
407 views

Conditional expectation: commuting integration and supremum

Let $X$ and $A$ be compact Polish spaces endowed with Borel $\sigma$-algebras. Let $\mathcal{A} = X\times \mathcal{B}(A)$ be the $\sigma$-algebra consisting of cylinders whose projections on $A$ are ...
Vokram's user avatar
  • 109
14 votes
1 answer
416 views

Lipschitz property of the determinant

$\newcommand{\A}{\mathcal A}\newcommand{\Tr}{\operatorname{tr}}$For $c$ and $C$ such that $0<c<C<\infty$, let $\A_{d;c,C}$ denote the set of all symmetric positive-definite real $d\times d$ ...
Iosif Pinelis's user avatar

1
2
3 4 5
16