7. Calculate the mgf, E(x), and Var(x) of the following nine distributions: Exponential Distribution
7. Calculate the mgf, E(x), and Var(x) of the following nine distributions: Exponential Distribution
Consider the following probability distribution for X. 7 0.1 0.1 0.2 003 0.2 0.1 (i) (ii) (iii) (iv) Find E(X). Find E(2X3+4x) Determine the MGF of X. Calculate Var (X) using MGF of X.
4 10 pts. Let X1 X2 be a random sample from the exponential distribution with parameter θ What is the mgf of Y = X1 + X2? a) (4 pts.+) Find E(Y-E(X1 + X2] using the mgf. For 2 more points on test 2: How is Y distributed?
4 10 pts. Let X1 X2 be a random sample from the exponential distribution with parameter θ What is the mgf of Y = X1 + X2? a) (4 pts.+) Find E(Y-E(X1...
Show that the following distributions belong to the exponential family. Find the natural parameter θ, scale parameter p and convex function b(9). Also find the E(Y) and Var(Y) as functions of the natural parameter. Specify the canonical link functions 1. Exponential distribution Bxp ), f(y:λ) λe-Ag. Binomial distribution known; f(y: π- C)π"(1-π)n-y, where n is 2. Bin(n,π). 3. Poisson distribution Pois(A), f(y:A)-e
Obtain E(Z|X), Var(Z|X) and verify that E(E(Z|X)) =E(Z),
Var(E(Z|X))+E(Var(Z|X)) =Var(Z)
3. Let X, Y be independent Exponential (1) random variables. Define 1, if X Y<2 Obtain E (Z|X), Var(ZX) and verify that E(E(Zx)) E(Z), Var(E(Z|X))+E(Var(Z|X)) - Var(Z)
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...
1. Suppose (x, Y) has bivariate normal distribution, E(x) E(Y)- 0, Var(X) σ , Var(Y) σ and Correl(X, Y) p. Calculate the conditional expectation E(X2|Y).
2. (a) Given that N-n, the conditional distribution of Y is x The unconditional distribution of N is Poisson (8). Calculate E(Y) and Var(Y). (b) A plant supervisor is interested in budgeting weekly repair costs for a certain type of machine. Records over the past years indicate that these repair cost have an exponential distribution with mean 20 for each machine studied. Let Y1, Y2, ..., Ysdenote the repair costs for five of these machines for the next week. Find...
A random variable X has the following mgf
et
M(t)=1−t, t<1.
(a) Find the value of ∞ (−1)k E(Xk).
(b) Find the value of E(2−X).
(c) Find the value of Var(2−X).
(d) Find the probability P (X > 4).
10. A random variable X has the following mgf М() t 1 1 t (a) Find the value of 1E(Xk) (b) Find the value of E(2X). (c) Find the value of Var(2-X) k 0 k! (d) Find the probability P(X >...
he second form for one-parameter exponential family distributions, introduced during lecture 09.1, was Jy (y | θ) = b(y)ec(0)t(y)-d(0) Let η = c(0). If c is an invertible function, we can rewrite (1) as where η is called the natural, or canonical, parameter and K(n) = d(C-1(n)). Expression (2) is referred to as the canonical representation of the exponential family distribution (a) Function κ(η) is called the log-normalizer: it ensures that the distribution fy(y n) integrates to one. Show that,...
(10%) Does there exist uniform distribution X with E[X] Var[X]? Explain! 1. =
(10%) Does there exist uniform distribution X with E[X] Var[X]? Explain! 1. =