6. The Poisson distribution is commonly used to model discrete data. The probability mass function of...
7. The Gamma distribution is commonly used to model continuous data. The probability density function of a Gamma random variable is f (zlo, β)- a. Find the MGF of a Gamma random variable. b. Use the MGF to find the mean of a Gamma random variable. c. Use the MGF to find the second raw moment of a Gamma random variable. d. Use results (b) and (c) to find the variance of a Gamma random variable. e. Let Xi, í...
Recall that a discrete random variable X has Poisson distribution with parameter λ if the probability mass function of X Recall that a discrete random variable X has Poisson distribution with parameter λ if the probability mass function of X is r E 0,1,2,...) This distribution is often used to model the number of events which will occur in a given time span, given that λ such events occur on average a) Prove by direct computation that the mean of...
The moment generating function (MGF) for a random variable X is: Mx (t) = E[e'X]. Onc useful property of moment generating functions is that they make it relatively casy to compute weighted sums of independent random variables: Z=aX+BY M26) - Mx(at)My (Bt). (A) Derive the MGF for a Poisson random variable X with parameter 1. (B) Let X be a Poisson random variable with parameter 1, as above, and let y be a Poisson random variable with parameter y. X...
6. (a) [5 pts] Show that the moment generate function of a Poisson distribution with parameter λ > 0 is M (t) eA(et-1) [Hint: You might need Σ¡ o a- ea, where k takes non-negative integer values.] (b) [5 pts) Use moment generating functions to prove that if Xi ~ Poisson(A1), X2 Poisson(A2), and Xi and X2 are independent, Xi+X2 Poisson(Ai+ A2).
I. Let X be a random sample from an exponential distribution with unknown rate parameter θ and p.d.f (a) Find the probability of X> 2. (b) Find the moment generating function of X, its mean and variance. (c) Show that if X1 and X2 are two independent random variables with exponential distribution with rate parameter θ, then Y = X1 + 2 is a random variable with a gamma distribution and determine its parameters (you can use the moment generating...
The moment generating function (MGF) for a certain probability distribution is given by 2 (2 + 2) , M(t) = R. t 2 Suppose Xi, X2, are iid random variables with this distribution. Let Sn -Xi+ (a) Show that Var(X) =3/2, i = 1,2. (b) Give the MGF of Sn/v3n/2. (c) Evaluate the limit of the MGF in (b) for n → 0. The moment generating function (MGF) for a certain probability distribution is given by 2 (2 + 2)...
3. (25 pts.) Let X1, X2, X3 be independent random variables such that Xi~ Poisson (A), i 1,2,3. Let N = X1 + X2+X3. (a) What is the distribution of N? (b) Find the conditional distribution of (X1, X2, X3) | N. (c) Now let N, X1, X2, X3, be random variables such that N~ Poisson(A), (X1, X2, X3) | N Trinomial(N; pi,p2.ps) where pi+p2+p3 = 1. Find the unconditional distribution of (X1, X2, X3). 3. (25 pts.) Let X1,...
Let X1, X2,..., X, be n independent random variables sharing the same probability distribution with mean y and variance o? (> 1). Then, as n tends to infinity the distribution of the following random variable X1 + X2 + ... + x, nu vno converges to Select one: A. an exponential distribution B. a normal distribution with parameters hi and o? C a normal distribution with parameters 0 and 1 D. a Poisson distribution
(1 point) In Unit 3, I claimed that the sum of independent, identically distributed exponential random variables is a gamma random variable. Now that we know about moment generating functions, we can prove it. Let X be exponential with mean A 4. The density is 4 a) Find the moment generating function of X, and evaluate at t 3.9 The mgf of a gamma is more tedious to find, so l'll give it to you here. Let W Gamma(n, A...
Problem 2 If Xi, X2. ,Xso be independent and idatically distributed with probability density function same as random variable X (x) = 1/2e-2x x > 0 and Y-X1 X2+X Points 5 Points) 5 Points a) Find Moment Generating Function of Y, My(S) b) What is MGF of-2x c What is MGF of 2X +3 Problem 2 If Xi, X2. ,Xso be independent and idatically distributed with probability density function same as random variable X (x) = 1/2e-2x x > 0...