SHOW THAT Z1,...,Zn be a random sample from N(0, 1), then z bar~N(0, 1/n)
SHOW THAT Z1,...,Zn be a random sample from N(0, 1), then z bar~N(0, 1/n)
Let's say (XL, Y)',.., (Xn,Yn)'(n > 2) is a random sample at Bivariate Normal Distribution ρσ102 41(ΑΓΑΝ! and r is sample correlation coefficient r- Also when Z and W, is as below, answer following questions (Question 3) (1) Show independence between (Z1, ..,Zn)' and (W, W)' (2) When (,,..,Zn)' and (Wi.,W' is independent, show Sww- Zw ~x2(n - 2), and show it is Szz ,Zn) independent with (Z1 Szw is independent, showNO,.1), and show it is 3) When (Z Z)...
Let Z1, Z2,.., Zn be independent Normal(0,1) random variables (a) Find the MGF for Z for all i (b) Find the MGF for (c) If n is even, find the PDF for Σ
2. Let Z1, Z2, Zn be independent Normal(0,1) random variables (a) Find the MGF for Z for all i (b) Find the MGF for Σ_1 Z (c) If n is even, find the PDF for ΣΙ_1 z?
Show that the mean X bar of a random sample of size n from a distribution having probability density function f(x;θ)=(1/θ)e-(x/θ) , ,0 < x < ∞ , 0 < θ < ∞ , zero elsewhere, is an unbiased estimator of θ and has variance θ2/n.
3 Minimum of IID exponentials Let Z1, ..., Zn be IID exponential random variables with mean 8. That is, each Zi has a PDF given by: f(3) = exp(-2/8], where z and B are positive. Derive the probability density function for min(21, ..., Zn) (i.e., the minimum of random variables 21, ..., Zn). You should find that the probability density function for min(Z1, ..., Zn) is that of an expo- nential random variable. What is the mean of min(Z1, ...,...
If Z is a continuous random variable, show that s2 converges to sigma2 as n goes to infinity. The value of s2 is (1/(n-1)) * the sum of (zi to z bar)2 from i = 1 to n.
Let Z1, Z2, . . . be a sequence of independent standard normal random variables. Define X0 = 0 and Xn+1 = (nXn + (Zn+1))/ (n + 1) , n = 0, 1, 2, . . . . The stochastic process {Xn, n = 0, 1, 2, } is a Markov chain, but with a continuous state space. (a) Find E(Xn) and Var(Xn). (b) Give probability distribution of Xn. (c) Find limn→∞ P(Xn > epsilon) for any epsilon > 0.
3 Minimum of IID exponentials Let Z1, ..., Zn be IID exponential random variables with mean 8. That is, each Z has a PDF given by: f(3) = exp(-z/B], where 2 and 3 are positive. x f(x) dx Derive the probability density function for min(Z......) (.e., the minimum of random variables 21,..., 2n). You should find that the probability density function for min(Z1,..., Zn) is that of an expo nential random variable. What is the mean of min(21,..., 2..)?
Let Y1<Y2<...<Yn be the
order statistics of a random sample of size n from the distribution
having p.d.f f(x) = e-y , 0<y<, zero elsewhere. Answer the following
questions.
(a) decide whether Z1 = Y2
and Z2=Y4-Y2 are
stochastically independent or not. (hint. first find the joint
p.d.f. of Y2 and Y4)
(b) show that
Z1 = nY1, Z2=
(n-1)(Y2-Y1),
Z3=(n-2)(Y3-Y2), ....,
Zn=Yn-Yn-1
are stocahstically
independent and that each Zi has the exponential
distribution.(hint use change of variable technique)
1. Let T-Σ-iz, where Z1,Zo, replacement from the set {1,2,... , N Show that ,Žm are numbers sampled at random without E(Zi) (N +1)/2 and hence E(T) m(N + 1)/2. Show that E(Z) 12 and hence - m)(N 12 Deduce that under the null hypothesis that F- G, the expectation and variance of Wilcoxon's two-sample test statistic are m(n+m+1)/2 and nm(n+m+1)/12, respectively.