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...
Suppose Y-X1-X2 where X1, x2 are iid Poisson(11) (a) Show that Y has moment generating function My (t) = e11(ette-t-2) (b) Even though you can do it from other results, use the mgf in (a) to find Var(Y).
7. Let Xn Xi++X2, where the Xi's are iid standard normal random variables (a) Show that Sn is a chi-square random variable with n de- grees of freedom. Hint: Show that X is chi-square with one degree of freedom, and then use Problem 6. (b) Find the pdf of (c) Show that T2 is a Rayleigh random variable. (d) Find the pdf for Ts. The random variable Ts is used to model the speed of molecules in a gas. It...
- Let {Xn} denote a sequence of iid random variables such that P(Xi = 1) = P(X1 = -1) = 1/2. Let Sn = X1 + X2 + ... + xn. (a) Find ES, and var(Sn); (b) Show that Sn is a martingale.
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...
Let ? have a Poisson(?) distribution. (a) Show that the moment generating function (mgf) of ? is given by ?(?) = exp[?(?? − 1)]. (b) Use the mgf found in (a) to verify that ?[?] = ? and ?[?] = ?.
1. The random variables Xi, X2,.. are independent and identically distributed (iid), each with pdf f given in Assignment 4, Question 1. Let Sn- Xi+.+X Using the Central Limit Theorem and the graph of the standard normal distribution in Figure 1, approximate the probability P(S100 >600). Express your answer in the format x.x-10-x. Verify your answer by simulating 10,000 outcomes of Si00 and counting how many of them are > 600. Show the code 1.00 0.95 0.90 0.85 1.2 1.4...
7. Let X a be random variable with probability density function given by -1 < x < 1 fx(x) otherwise (a) Find the mean u and variance o2 of X (b) Derive the moment generating function of X and state the values for which it is defined (c) For the value(s) at which the moment generating function found in part (b) is (are) not defined, what should the moment generating function be defined as? Justify your answer (d) Let X1,...
4. The moment generating function of the normal distribution with parameters μ and σ2 is (t) exp ( μ1+ σ2t2 ) for -oo < t oo. Show that E X)-ψ(0)-μ and Var(X)-ψ"(0)-[ty(0)12-σ2. 5. Suppose that X1, X2, and X3 are independent random variables such that E[X]0 and ElX 1 for i-12,3. Find the value of E[LX? (2X1 X3)2] 6. Suppose that X and Y are random variables such that Var(X)-Var(Y)-2 and Cov(X, Y)- 1. Find the value of Var(3X -...
1. (Wasserman: Exercise 3.8.24) Let X1, X2,..., Xn be IID Exponential(B). Find the moment generating func- tion (MGF) of Xi. Prove that Σ¡_1 Xi ~ Gamma(n,d),
9 Let Xi, X2, ..., Xn be an independent trials process with normal density of mean 1 and variance 2. Find the moment generating function for (a) X (b) S2 =X1 + X2 . (c) Sn=X1+X2 + . . . + Xn. (d) An -Sn/n 9 Let Xi, X2, ..., Xn be an independent trials process with normal density of mean 1 and variance 2. Find the moment generating function for (a) X (b) S2 =X1 + X2 . (c)...