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2 answers
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is this process a Markov one?

Here is the problem I can't solve. Let $\xi_n$ $(n=1,2,3,\dots)$ be a sequence of i.i.d. random variables on $\mathbb{R}$ with density $p(x)>0$, let $\eta_n=\sum_{i=1}^{n}\xi_i^2$. Define $$\...
I.Kiaan's user avatar
  • 21
2 votes
3 answers
376 views

Generations until fixation: A nontrivial generalization of a dice convergence problem

In spite of its "recreational" aspect, this question appears to me to be research-level and (I hope) clearly formulated and tagged. Edit 4/4/20: You can find a related question with the ...
Benjamin Dickman's user avatar
6 votes
1 answer
361 views

Random walks on infinite directed regular graphs

Let us consider a directed graph $\Gamma=(V,E,s,t)$ ($V$ set of vertices, $E$ set of edges, $s,t: E \rightarrow V$ are the "source" and "target" maps). Assume that $\Gamma$ is bi-regular, that is ...
Joël's user avatar
  • 26k
0 votes
1 answer
203 views

Law of large numbers for Harris recurrent Markov chains

I'm trying to familiarize myself with the details of the proof that the Markov chains produce by the Metropolis-Hastings algorithm have a law of large numbers. I've found a half dozen or more ...
R Hahn's user avatar
  • 2,791
3 votes
3 answers
163 views

A stopping time that gives the metric

Let $\Omega$ a finite metric space with $\forall x,y,z\in \Omega:d(x,y)<d(x,z)+d(z,y)$. Does there exists a continuous-time Markov process $X$ on $\Omega$ such that $$\mathbb{E}_x(T_y)=d(x,y)$$ for ...
RaphaelB4's user avatar
  • 4,361
2 votes
1 answer
185 views

Entropy rate problem of ergodic Markov process with non-ergodic joint

I have a problem with the entropy rate when two ergodic Markov processes who are independent of each other having a non-ergodic joint. More specifically let us consider two finite-state Markov ...
Yi Huang's user avatar
  • 333
0 votes
2 answers
244 views

Spectrum of a Markov kernel acting on $L^2$

Let $P$ be a Markov kernel on a measurable space $(E,\mathcal E)$ admitting an invariant probability measure $\pi$. $P$ acts on $L^2(\pi)$ via $$Pf:=\int\kappa(\;\cdot\;{\rm d}y)f(y).$$ The invariance ...
0xbadf00d's user avatar
  • 167
2 votes
1 answer
290 views

Uniform upper bound on contraction coefficient w.r.t total-variation metric, of a certain set of block-diagonal Markov kernels

Disclaimer. This is related to another question I've asked on the TCS site https://cstheory.stackexchange.com/q/46097/44644. I'm new to information theory (and other relevant fields). It's even ...
dohmatob's user avatar
  • 6,853
1 vote
1 answer
284 views

Symmetric random walks - bounds on the amount of time spent in a subset $A$?

For a symmetric random walk $S_n$, if we have a bound $P(S_n \in A) < \delta$, do we get a bound on the amount of time $S_n$ spends in $A$? Let $S_n$ be a symmetric random walk on the integers. ...
user avatar
1 vote
0 answers
73 views

Reduce the asymptotic variance for a class of Metropolis-Hasting estimates

I'm running the Metropolis-Hastings algorithm with state space $E$, target distribution $\mu=p\lambda$ and proposal kernel $Q$ to estimate $\mu(hf)$ for a fixed function $f:E\to[0,\infty)^3$ and a ...
0xbadf00d's user avatar
  • 167
1 vote
0 answers
106 views

Show a Poincaré inequality for a Markov kernel and minimize the Poincaré constant

Let $\tilde\kappa$ denote the transition kernel of the Markov chain generated by the Metropolis-Hastings algorithm with proposal kernel $\tilde Q$ and target distribution $\tilde\mu$ (see definitions ...
0xbadf00d's user avatar
  • 167
1 vote
0 answers
56 views

Minimizing the rate of geometric ergodicity of a Metropolis-Hastings kernel depending on a parameter

Let $\tilde\kappa$ denote the transition kernel of the Markov chain generated by the Metropolis-Hastings algorithm with proposal kernel $\tilde Q$ and target distribution $\tilde\mu$. I want to ...
0xbadf00d's user avatar
  • 167
1 vote
1 answer
143 views

Comparison of hitting probability of two Markov chains both with only one absorbing state version 2 under stronger condition

Let $N_n:=\{1,2,\cdots,n\}$. Given two finite states Markov chains $\big(X^{(j)}_i\in N_n\}\big)_{i=0}^\infty$ for $j\in\{1,2\}$, both of which have two absorbing states at $1$ and $n$. $\text{Pr}\...
Hans's user avatar
  • 2,239
1 vote
1 answer
119 views

Comparison of hitting probability of two Markov chains both with only one absorbing state

Let $N_n:=\{1,2,\cdots,n\}$. Given two finite states Markov chains $\big(X^{(j)}_i\in N_n\}\big)_{i=0}^\infty$ for $j\in\{1,2\}$, both of which have one absorbing state $1$. Pr$(X^{(1)}_{i+1}=1|X_i=1)...
Hans's user avatar
  • 2,239
1 vote
1 answer
170 views

Stationary distribution of Markov Chain with departure

I have a Markov Chain of $N$ states. Such states represent the energy levels in a molecule. The states' connectivity is as follows: States $j\in\{0,\ldots,N\}$ transition to $k\in\{\max(j-M,0),...,\...
TheVal's user avatar
  • 151
0 votes
1 answer
82 views

In smooth stochastic dynamics, if a Lebesgue-like measure is both forward-time and reverse-time stationary, is the measure necessarily incompressible?

Let $(\Omega,\mathcal{F},\mathbb{P})$ be a probability space and let $X$ be a compact connected $C^\infty$-smooth manifold. Let $F \colon \Omega \times X \to X$ and $\bar{F} \colon \Omega \times X \to ...
Julian Newman's user avatar
0 votes
1 answer
95 views

If a probability measure is stationary in both forward time and reverse time, does this imply that the measure is incompressible?

Let $(\Omega,\mathcal{F},\mathbb{P})$ be a probability space and let $X$ be a compact metric space. Let $F \colon \Omega \times X \to X$ and $\bar{F} \colon \Omega \times X \to X$ be measurable ...
Julian Newman's user avatar
0 votes
2 answers
128 views

Markov with epsilon memory and Quantitative Strong Markov property

We have a process $\{X_{t}\}_{t\geq 0}$ ,with fixed parameter $\epsilon>0$, starting from zero that satisfies The process is strictly monotone $X_{t+r}-X_{t}>0$ with moments existing $p\in(-\...
Thomas Kojar's user avatar
  • 5,474
0 votes
1 answer
80 views

A question about positive operator pregenerator [closed]

Thank you for reading. My question was raised up when I tried to prove an example in the book of Liggett(1985), which is in P13 Example 2.3(a). Here is a link of the page: https://books.google.com/...
Chennes's user avatar
  • 385
1 vote
1 answer
174 views

Coupling argument involved in the contracting and mixing properties of the Glauber dynamics for an Ising model

While doing a research work, I had to read about the Glauber dynamics for an Ising model. A wonderful account on this is given in the book Markov Chains and Mixing Times by Levin, Peres and Wilmer. ...
abcd's user avatar
  • 367
2 votes
0 answers
321 views

Why do we assume that $\mathcal{A}$ is an algebra in this 2003 paper of Bobkov and Tetali?

In Bobkov and Tetali - Modified Log-Sobolev Inequalities, Mixing and Hypercontractivity (extended version Modified Logarithmic Sobolev Inequalities in Discrete Settings), at the beginning of section 3,...
Ella Sharakanski's user avatar
2 votes
1 answer
409 views

Existence and uniqueness of a stationary measure

This same question was also posted on MSE https://math.stackexchange.com/questions/3327007/existence-and-uniqueness-of-a-stationary-measure. Recently I have posted the following question on MO ...
Matheus Manzatto's user avatar
2 votes
0 answers
113 views

Characterizing the relationship between element-wise Markov transitions and the full-conditionals of the stationary distribution

Consider a $p$ dimensional random variable with a discrete support. Consider a Markov transition kernel on the state space that is defined in terms of element-wise transition distributions. One can ...
R Hahn's user avatar
  • 2,791
1 vote
1 answer
173 views

Can we show that $\mathbb R^{\mathbb N}\ni x\mapsto\bigotimes_{n\in\mathbb N}\mathcal N_{x,\:\sigma^2}$ is a Markov kernel?

Let $\sigma>0$ and $\mathcal N_{x,\:\sigma^2}$ denote the normal distribution with mean $x\in\mathbb R$ and variance $\sigma^2$. From the Ionescu-Tulcea theorem, we know that $$\kappa(x,\;\cdot\;):=...
0xbadf00d's user avatar
  • 167
1 vote
4 answers
272 views

Probability of traversing all other states and finally landing on one state

This is a cross-post from math.stackexchange.com. There has been no response there. Given a Markov chain of finite states with constant transition probabilities, what is the method to compute the ...
Hans's user avatar
  • 2,239
0 votes
0 answers
83 views

A closed form of mean-field equations

Assume that a system at time t, for example number of costumers in a line at time $t$ which is denoted by $q(t)$, follows a Markov chain with these dynamics (probabilities) $$P(q(t+\Delta t)-q(t)=1)=\...
user avatar
7 votes
2 answers
259 views

Slowest initial state for convergence of finite birth-and-death Markov chains

Consider the continuous-time birth-and-death Markov chain on $\{1,\cdots,n\}$ with all rates equal to $1$. Is it true that the convergence to equilibrium, in total variation distance, is slowest when ...
Guillaume Aubrun's user avatar
5 votes
1 answer
199 views

Reference request: When is the variance in the central limit theorem for Markov chains positive?

I'm looking for a reference which gives sufficient conditions for the variance to be positive in the central limit theorem for Markov chains (cf https://en.wikipedia.org/wiki/...
munchhausen's user avatar
3 votes
0 answers
88 views

Joint drunkard walks

The drunkard walk is a game where two players have $a$ and $b$ dollars, respectively, and they play a series of fair games (both risking one dollar in each game) until one of them goes broke. My ...
A. Pongrácz's user avatar
0 votes
2 answers
306 views

Lower bounds on discrete time finite Markov chains hitting probabilities

I am interested in some general theorems related to lower bounds on discrete time finite Markov chains hitting probabilities (preferably ergodic chains , but not necessarily ), with references . ...
Cristian Dumitrescu's user avatar
3 votes
1 answer
226 views

Total offspring of Poisson multitype branching process

A normal branching process $Z_n$ initialized with $Z_0=1$ and offspring generated from $Pois(p),p<1,$ has a total progeny / total off spring distribution $$X=\sum_{n=0}^\infty Z_n$$ $X\in \mathbb{...
Conformal's user avatar
  • 315
2 votes
1 answer
994 views

Comparing mixing time of lazy and non-lazy Markov chains

Suppose we have a probability distribution $\pi : X \rightarrow [0,1]$ where $X$ is finite and let $Q : X \times X \rightarrow [0,1]$ be a Markov kernel that is reversible with respect to $\pi$. That ...
Josh R's user avatar
  • 123
2 votes
0 answers
70 views

If $X^n$ is a sequence of càdlàg processes whose FDDs converge to a continous process $X$, does $X^n$ converge to $X$ in the Skorohod topology?

Let $(\Omega,\mathcal A,\operatorname P)$ be a probability space, $E$ be a complete locally compact separable metric space, $(X^n_t)_{t\ge0}$ be an $E$-valued càdlàg process on $(\Omega,\mathcal A,\...
0xbadf00d's user avatar
  • 167
2 votes
0 answers
37 views

Exclusion processes from point of view of a tagged particle

I'm interested in the simple exclusion processes on $Z^d$ and the ergodic theorems that can be proved from the point of view of the particle. Ellen Saada proved the following in 1987 (Annals of Prob): ...
arjun's user avatar
  • 941
3 votes
1 answer
236 views

Mixing time and spectral gap for a special stochastic matrix

Consider the following dimension stochastic matrix, \begin{bmatrix} p & q & 0 & 0 & 0 \\ 0 & 0 & 1 & 0 & 0 \\ 0 & 0 & 0 & 1 & 0 \\ 0 & 0 & 0 &...
Hao Yuan's user avatar
  • 103
4 votes
2 answers
206 views

Reference on a markov chain / Queue

Im looking for a reference that treats the Markov Chain defined by $$W_i=(W_{i-1}-1)\vee X_i$$ where $X_i\geq 0$ are i.i.d discrete variables. In particular im interested in a reference that treats ...
Conformal's user avatar
  • 315
0 votes
1 answer
204 views

How is the Cauchy-Schwarz inequality used in the proof of Lyapunov's criterion in the book "Analysis and Geometry of Markov Diffusion Operators"

Let $(E,\mu,\Gamma)$ be a full Markov triple (see definition below), $J\in\mathcal A$ with $J\ge1$ and $g\in\mathcal A_0$. In the proof of Theorem 4.6.2 of the book "Analysis and Geometry of Markov ...
0xbadf00d's user avatar
  • 167
1 vote
1 answer
305 views

Existence of a Lyapunov function for a log-concave measure

Let $d\in\mathbb N$, $f:\mathbb R^d\to\mathbb R$ be convex with $$\int e^{-f(x)}\:{\rm d}x<\infty\tag1$$ and $\mu$ denote the measure with density $e^{-f}$ with respect to the Lebesgue measure on $\...
0xbadf00d's user avatar
  • 167
4 votes
5 answers
7k views

Proof of Bellman optimality equation for finite Markov Decision Processes

This question has already been posed in Cross Validated without receiving a correct formal answer, so I reformulate it here to gain attention of mathematicians. I am referring to chapter 3 of Sutton ...
hardhu's user avatar
  • 171
1 vote
0 answers
81 views

If $\text P\left[X_2\in B_2\mid X_1\right]=\kappa(X_1,B_2)$ a.s. for all $B_2$, can we select a common null-set over all $B_2$?

Let $(\Omega,\mathcal A,\operatorname P)$ be a probability space $(E_i,\mathcal E_i)$ be a measurable space $X_1:\Omega\to E_1$ $X_2:\Omega\to E_2$ be $(\mathcal A,\mathcal E_2)$-measurable $\kappa$ ...
0xbadf00d's user avatar
  • 167
-1 votes
1 answer
370 views

What's the probability of two independent events in time domain?

Suppose there are two independent events A and B. The probability that A or ...
oleotiger's user avatar
1 vote
0 answers
79 views

Discrete Markov process on finite interval

Consider an contiguous array of $N$ states, numbered from $1$ to $N$. At every time step $t$, the process should transition to an adjacent state. The probability of moving to the right (from state $n\...
xntric_ngneer's user avatar
2 votes
0 answers
416 views

How can we treat the generator of a discrete-time Markov chain as the generator of a Markov-jump process?

In the popular paper Weak Convergence and Optimal Scaling of Random Walk Metropolis Algorithms by Roberts, Gelman and Gilks, the authors state (see below) that "in the Skorokhod topology, it does not ...
0xbadf00d's user avatar
  • 167
3 votes
2 answers
264 views

Probability of one species reaching zero before the other in a Markov process on a 2d lattice

$\textbf{Background}$: Say we've got a two-variable system of stochastic chemical reactions, with quantities $\vec{x}(t) = (x_1(t),x_2(t)) \in \mathbb{N}^2$ evolving according to the following system, ...
Bianca's user avatar
  • 41
1 vote
0 answers
149 views

Construction of Feller's pseudo-poisson process

Let $(\Omega,\mathcal A,\operatorname P)$ be a probability space $(E,\mathcal E)$ be a measurable space $(Y_n)_{n\in\mathbb N_0}$ be a $(E,\mathcal E)$-valued time-homogeneous Markov chain on $(\...
0xbadf00d's user avatar
  • 167
3 votes
2 answers
1k views

Non-backtracking random walk in regular (finite) graphs

I know that many things are known when dealing with random walks on a finite (or even infinite) graph: mixing time, returns to origin, etc. All is based in the use of the Markovian property of such a ...
Johnny Cage's user avatar
  • 1,561
1 vote
0 answers
120 views

Existence of Time-Reversed Markov Kernels

Suppose I have a probability measure $\pi$ and a Markov kernel $q$ which leaves $\pi$ invariant, in the sense that \begin{align} \int_x \pi(dx) q(x \to dy) = \pi(dy) \end{align} Then, a (the) time-...
πr8's user avatar
  • 801
1 vote
2 answers
302 views

how to derive stationary distribution of maximal entropy random walk

I was reading the paper 0810.4113v2, burda, which analyzed the stationary distribution maximal entropy random walk on the irregular lattice. I am confused on some of the steps. Description: The ...
Nick Dong's user avatar
  • 211
2 votes
0 answers
37 views

Reference request: semimarkov processes

What are some good modern introductions to the theory of semimarkov processes? To be clear, by a semimarkov processes, I mean a Markov chain, together with "waiting times" between transitions, the ...
Simon Segert's user avatar
3 votes
1 answer
97 views

Bounds on $\|(P+\Delta)^n - P^n\|_F$ for stochastic matrices

Let us suppose that $P$ is a stochastic matrix (non-negative matrix with $P \mathbf{1} = \mathbf{1}$). Let $\Delta$ such that $P + \Delta$ is a stochastic matrix (which means $P + \Delta$ is non-...
mfrt's user avatar
  • 113

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