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3 votes
1 answer
130 views

Exercise on Girsanov's theorem

currently I am trying to solve the following exercise. Exercise: Let $b : \mathbb R → \mathbb R$ be Lipschitz, and let $t \mapsto X(t)$ be the unique strong solution of the 1-dimensional SDE given by $...
a.s. graduate student's user avatar
0 votes
0 answers
46 views

Give a lower bound using Chebyshev's inequality

So I am having problems with this exercise. Can someone help me? The waiting time $T$ in hours for the order in the pizzeria DaFranco has the following density function: $f_T(X):=\left\{\begin{matrix} ...
Marco Di Giacomo's user avatar
0 votes
1 answer
30 views

How to find the right probability measure and how to be able to distinguish $A \cap B$ from $A|B$

Three machines produce the same car parts and have the following production shares and defect rates: A part from the total production is selected at random. a) Set up a suitable model $(Ω, F, P)$ ...
Marco Di Giacomo's user avatar
1 vote
1 answer
40 views

Some exercises with a random variable $Z(w)=\left\{\begin{matrix} X(w)& \mbox{if}\ Y(w)\geq 0 \\ -X(w)&\mbox{if} \ Y(w)<0 \end{matrix}\right.$

Hey I want to check my solutions for this problem: Let $X$ and $Y$ be independent standard normally distributed random variables on a probability space $(\Omega, \mathcal F, \mathbb P)$ and define $Z(...
Marco Di Giacomo's user avatar
0 votes
1 answer
47 views

Expected value, variance and covariance with discrete random variables

I wamted to check my solutions for this problem: The joint distribution of the random variables $X$ and $Y$ is given by: Calculate $E[X], E[Y], Var(X),Var(Y),Cov(X,Y)$ So for $E[X]=1/8+1/4+2(1/8+1/2)=...
Marco Di Giacomo's user avatar
0 votes
2 answers
50 views

Solution verification with conditional probability problem

I want to check my solutions for this problem: After a weekend seminar, some participants go to a restaurant together on the last evening. $53\%$ of the male seminar participants take part, for the ...
Marco Di Giacomo's user avatar
0 votes
1 answer
44 views

Solutions verification on a problem about probability

I want to check my solutions for this problem. Klaus and Anna throw tetrahedrons (bodies with 4 triangles as faces) at the same time. Klaus throws 2 tetrahedrons and Anna throws one. What is the ...
Marco Di Giacomo's user avatar
1 vote
1 answer
50 views

Questions on the construction of a stochastic model

I want to check my solutioons for this problem: The captain of a soccer team is in good form $70%$ of the games, in fair form $20%$ and in poor form $10%$. In these cases, the team's chances of ...
Marco Di Giacomo's user avatar
1 vote
1 answer
194 views

Problems in finding the marginal distribution

I have some problems with this exercise: Let $X$ and $Y$ be real-valued random variables with a common density: $f_{X,Y}=\left\{\begin{matrix} 2e^{-x-y} & 0<y<x \\ 0 & else \end{matrix}\...
Marco Di Giacomo's user avatar
0 votes
0 answers
34 views

Calculating distribution and expected values of minimum and maximum of independent uniform random variables

I am having some problems with this exercise, can someone help me? Let $X_1,X_2$ be independent and identically uniform on $[0,a]$. Let $U:= \min(X_1,X_2)$ and $V:= \max(X_1,X_2)$. Calculate the ...
Marco Di Giacomo's user avatar
1 vote
1 answer
49 views

Convergence Properties of Sums of iid Random Variables" [duplicate]

I want to check my solutions for this problem. Can someone help me? Let $(X_n)_{n\geq1}$ be independent and identically distributed real-valued random variables. Suppose $E[|X_n|] = ∞$. a. Show that $...
Marco Di Giacomo's user avatar
1 vote
1 answer
66 views

Show that $P(|X_n| > an \text{ for infinitely many } n) = 1$ for any $a > 0$ with $E[|X_n|] = ∞$

I want to check my solutions for this problem. Can someone help me? Let $(X_n)_{n\geq1}$ be independent and identically distributed real-valued random variables. Suppose $E[|X_n|] = ∞$. a. Show that $...
Marco Di Giacomo's user avatar
1 vote
0 answers
33 views

Probability Measure and Algebraic Structure in Infinitely Repeated Coin Tosses

Hey I want to check my solutions for this problem: Consider the sample space $\Omega = \{0, 1\}^N$ of an infinitely repeated coin toss. Let $Π_n: \Omega \rightarrow \{0, 1\}^n$ be the coordinate ...
Marco Di Giacomo's user avatar
2 votes
1 answer
468 views

Law of Large Numbers for a Brownian Motion

I am self-learning introductory stochastic calculus from A first course in Stochastic Calculus by L.P.Arguin. The part(c) of the below exercise problem on the time-inversion property of Brownian ...
Quasar's user avatar
  • 5,450
4 votes
0 answers
57 views

How can I show that $\bigcap_{n\geq 0} \sigma(X_n,X_{n+1}...)=\sigma(X)$?

Let $X$ be a uniformly distributed random variable in $[0,1]$ and define $X_n:=\lfloor 2^nX\rfloor 2^{-n}$ for all $n$. I want to show that $\bigcap_{n\geq 0} \sigma(X_n,X_{n+1}...)=\sigma(X)$. My ...
user1294729's user avatar
  • 2,018

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