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1 vote
0 answers
42 views

Optimal matching of Bernoulli random variables

Let $Z_1$, ..., $Z_n$ be a sequence of independent Bernoulli random variables such that for all $i\in\left\{1,..,n\right\}$ $Z_i\sim\mathcal{B}(p_i)$ where $p_i < 1/2$. Define $l(x_{1:n}, y_{1:n}) =...
0 votes
1 answer
100 views

Conditional expectation with random variables from different Probability spaces [closed]

Let $(X,\mathcal{F}_X,\mathbb{P})$ and $(Y,\mathcal{F}_Y,\mathbb{Q})$ be two probability spaces. I know that the expectation of random variable $Z:X\rightarrow \mathbb{R}$ is affected by the random ...
1 vote
0 answers
44 views

Renewal reward process's reward tail probability

Suppose we are given a dice with $K$ faces, denoted by $k=1,\dots,K$, where the probability of realizing a face $k$ is $p_k\in[0,1]$ with $\sum_{k=1,\dots,K}p_k=1$. Now, we roll the dice repetitively. ...
1 vote
1 answer
106 views

Probability that a probability will be less than a certain value

Suppose I have a nonnegative random variable $X$ and I don't know its expected value, but I know that its expected value is less than or equal to $a$ with at least probability $p^*$. i.e, $\mathbb{P}(\...
0 votes
1 answer
33 views

Markov Chain Detailed Balance $\pi(x)*P(x, y) = \pi(y)*P(y, x)$

Let's say I have a Markov chain and it has a transition matrix denoted as $P$. The $(row, column)$ elements of the $P$ matrix are denoted as $P(i, j)$. Just by looking at the transition matrix $P$, ...
0 votes
2 answers
46 views

Probability 2 earthquakes happen in a period of time.

The amount of earthquakes that happen at island X follows the Poisson process with mean 2 . Given that 2 earthquakes have happened in this year, find the probability both the earthquakes happen ...
1 vote
1 answer
13 views

Expectation of the process adapted to the filtration of the Wiener process

Suppose $\sigma_t$ is a stochastic process adapted to the filtration $\mathcal{F}_t$ generated by the Wiener process $W_t$. I would like to know how to compute the following expectation: $$E = \mathbb{...
2 votes
0 answers
35 views

Difference between compensator of point process under real parameter an its MLE estimator

Suppose we have some point process $N=N_{\theta_0}$ on the real line, driven by a conditional intensity $\lambda_{\theta_0}$ dependent on some finite-dimensional parameter $\theta_0\in\Theta\subset\...
2 votes
1 answer
56 views

Convergence of weighted sum to Brownian Motion

Let $\{\varepsilon_t\}_{t = 1}^T$ be a sequence of iid random variables such that $\varepsilon_t \sim N(0, \sigma^2)$ and $\sigma^2 > 0$. Then it is known that (see 17.3.6 in James Hamilton's Time ...
3 votes
1 answer
965 views

Two independent Poisson processes.

I am trying to prove the result that exactly $k$ occurrences of a Poisson process before the first occurrence of another independent Poisson process is a geometric random variable. \begin{align} &...
0 votes
1 answer
2k views

What is the probability of getting the same side n times in a row in a coin toss

Assuming everything is fair what are the odds that one of the two sides in a coin toss wins 6 times in a row within the first 6 tosses? Please also answer for the general case ...
1 vote
0 answers
95 views

Unbiased Cumulant Estimate - Fifth Cumulant

I am searching the definition of the $5^{th}$ unbiased cumulant estimate. Let $K_j$, be the $j$-th unbiased cumulant estimate of a probability distribution, based on the sample moments. Let $m_j$ be ...
0 votes
1 answer
38 views

Sub-Gaussian $X_t$, prove $\mathbb{E}\left[\sup_{t\in T}X_t \right] \leq 2 \mathbb{E}\left[\sup_{\rho(t,s)\leq \delta}(X_t-X_s) \right]+J(\delta,T)$

This is a question-and-answer just for me, but if you have alternate answers or comments, feel free to share them. Let $(T,\rho)$ be a metric space and $\{X_t\}_{t\in T}$ be a sub-Gaussian process ...
0 votes
1 answer
46 views

A Gaussian process and a Rademacher proecss are sub-Gaussian

This is a question-and-answer just for me, but if you have alternate answers or comments, feel free to share them. Let $(T,\rho)$ be a metric space and $\{X_t\}_{t\in T}$ be a stochastic process ...
4 votes
0 answers
53 views

When $X_t$ is conditionally normal distributed and has density $p_t$, how can we compute $\text E\left[\left\|\nabla\ln p_t(X_t)\right\|^2\right]$?

Let $d\in\mathbb N$ and $(X_t)_{t\ge0}$ be an $\mathbb R^d$-valued process. Assume $$\operatorname P\left[X_t\in\;\cdot\;\mid X_0\right]=\mathcal N(X_0,\Sigma_t)\tag1$$ for some covariance matrix $\...

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