Suppose
are three independent random variable from a Normal distribution
with mean
and variance
.Then as we know,
.
Hence each of
and
is unbeased for the same population parameter
.
4. (12 pts) Give an example of three distinct random variables where each is an unbiased...
Let X1, ..., Xn be independent N(θ, θ^2) random variables where θ > 0 is a parameter. Find the Maximum Likelihood Estimator (MLE) of the parameter θ. Is the estimator of θ: a) unbiased? b) efficient? c) sufficient? d) consistent? Justify your answers. Include the definitions and theorems that you use in your answers. When working through this problem we had an issue with finding a MLE that didn't involve an imaginary number.
Question 4 0.8 pts Suppose Ô is an estimator for the population parameter 4. Which of the following is true for us to Say that Ô is an unbiased estimate of e? Elên) = 0 None of the options must be true Elê) = Elê) < Elo), Question 5 0.8 pts Which of the following is a threat to validity of the instrumental variables method?
Please give detailed steps. Thank you.
5. Let {X1, X2,..., Xn) denote a random sample of size N from a population d escribed by a random variable X. Let's denote the population mean of X by E(X) - u and its variance by Consider the following four estimators of the population mean μ : 3 (this is an example of an average using only part of the sample the last 3 observations) (this is an example of a weighted average)...
QUESTION 5 Suppose that Yı, Y2,.., Yn independent variables such that where β is an unknown parameter, X1, x2-.., xn are known real numbers, and el,e2 independent random errors each with a normal distribution with mean 0 and variance ơ2 ,en are (a) Show that is an unbiased estimator of β. What is the variance of the estimator? (b) Given that the probability density function of Y is elsewhere, show that the maximum likelihood estimator of β is not the...
Let Y, Y2, Yz and Y4 be independent, identically distributed random variables from a population with mean u and variance o. Let Y = -(Y, + Y2 + Y3 +Y4) denote the average of these four random variables. i. What are the expected value and variance of 7 in terms of u and o? ii. Now consider a different estimator of u: W = y + y + y +Y4 This an example of weighted average of the Y. Show...
12. Let X and Y be independent random variables, where X has a uniform distribution on the interval (0,1/2), and Y has an exponential distribution with parameter = 1. (Remember to justify all of your answers.) (a) What is the joint distribution of X and Y? (b) What is P{(x > 0.25) U (Y > 0.25)}? (c) What is the conditional distribution of X. given that Y - 3? (d) What is Var(Y - E[2X] + 3)? (e) What is...
7. (12 points) Let Yı,Y2, ..., Yn be a random sample from Gamma(a,b), where a = 2 and 3 is an unknown parameter. 2 (a) Find the method of moments (MOM) estimator of B. (b) Find the maximum likelihood estimator (MLE) of B. (€) Are the estimators in parts (a) and (b) MVUEs for B? Justify your answer.
4. (24 marks) Suppose that the random variables Yi,..., Yn satisfy Y-B BX,+ Ei, 1-1, , n, where βο and βι are parameters, X1, ,X, are con- stants, and e1,... ,en are independent and identically distributed ran- dom variables with Ei ~ N (0,02), where σ2 is a third unknown pa- rameter. This is the familiar form for a simple linear regression model, where the parameters A, β, and σ2 explain the relationship between a dependent (or response) variable Y...
Problem 4. (5 pts) Continuous Random Variables (a) (2 pt) If X is uniform on [0, 1], then for what function f is f(x) exponential with parameter 12 (b) (3 pts) If X, Y are independent standard normal random variables N(0,1), what is the density of X - Y?
12. Let X and Y be independent random variables, where X has a uniform distribution on the interval (0,1/2), and Y has an exponential distribution with parameter A= 1. (Remember to justify all of your answers.) (a) What is the joint distribution of X and Y? (b) What is P{(X > 0.25) U (Y> 0.25)}? nd (c) What is the conditional distribution of X, given that Y =3? ur worl mple with oumbers vour nal to complet the ovaluato all...