


1. Let X1 ~N(1,2) and X2 ~N(-1,2) be two Gaussian variables, and let Z = X1 +X2. (a) Express FX1 ...
3 -0.751 (X1,X2, X3) be jointly Gaussian with ux (1,-2,3) and Cx 1. Let X = 3 0.25 4 L-0.75 0.25 Hint: If a set of random variables (RVs) are jointly Gaussian, then any subset of those RVs are also jointly Gaussian. Similarly, adding constants to (or taking linear combinations of) jointly Gaussian RVs results in jointly Gaussian RVs. Using this property you can solve problem 1 without using integration. When appropriate, you may express your answer by saying that...
Let X1 and X2 be two discrete random variables, where X1 can
attain values 1, 2, and 3, and X2 can attain values 2, 3 and 4. The
joint probability mass function of these two random variables are
given in the table below: X2 X1 2 3 4 1 0.05 0.04 0.06 2 0.1 0.15
0.2 3 0.2 0.1 0.1 a. Find the marginal probability mass functions
fX1 (s) and fX2 (t). b. What is the expected values of X1...
From 5.5-6. Let X1 N(4.2, 1) and X N (12,70) be two Gaussian random variables. (1) Sketch the PDFs of X1, X2 on the same chart. (2) Assuming Xi, X2 are independent, compute P[Xi > X2
The joint density of random variables X1, X2 is given by fx1,x2 (x1, 2)= 6x1, for 0 < xı < 1, 0 2 <1 - r Let Y X1X2. Find the joint density of Yi and Y2 Х1, Y?
Let X1 and X2 have the joint pdf as fX1,X2 (x1, x2) = e −(x1+x2) , 0 < x1 < ∞, 0 < x2 < ∞. Find the pdf of X1 + X2 through the following two-step procedure. (a) Find the joint pdf of Y = X1 + X2 and Z = X2, and specify the domain. (b) Find the marginal pdf of Y = X1 + X2.
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,...
5. Let Xi i = 1,2, . ,N be i.i.d. U(0,1). Let Z = max{X1, .,Xn} and find Fz.
Let Ņ, X1. X2, . . . random variables over a probability space It is assumed that N takes nonnegative inteqer values. Let Zmax [X1, -. .XN! and W-min\X1,... ,XN Find the distribution function of Z and W, if it suppose N, X1, X2, are independent random variables and X,, have the same distribution function, F, and a) N-1 is a geometric random variable with parameter p (P(N-k), (k 1,2,.)) b) V - 1 is a Poisson random variable with...
4 points) Let X1, X2 be independent random variables, with X1 uniform on (3,9) and X2 uniform on (3, 12). Find the joint density of Y = X/X2 and Z = Xi X2 on the support of Y, Z. f(y, z) =
Let X1,X2 be two independent
exponential random variables with λ=1, compute the
P(X1+X2<t) using the joint density function. And let Z be gamma
random variable with parameters (2,1). Compute the probability that
P(Z < t). And what you can find by comparing P(X1+X2<t) and
P(Z < t)? And compare P(X1+X2+X3<t) Xi iid
(independent and identically distributed) ~Exp(1) and P(Z < t)
Z~Gamma(3,1) (You don’t have to compute)
(Hint: You can use the fact that Γ(2)=1,
Γ(3)=2)
Problem 2[10 points] Let...