Problem 2. (26 points) Two random variables X and Y are jointly normally distributed, with E(X)x,...
Q2 Suppose X1, X2, ..., Xn are i.i.d. Bernoulli random variables with probability of success p. It is known that p = ΣΧ; is an unbiased estimator for p. n 1. Find E(@2) and show that p2 is a biased estimator for p. (Hint: make use of the distribution of X, and the fact that Var(Y) = E(Y2) – E(Y)2) 2. Suggest an unbiased estimator for p2. (Hint: use the fact that the sample variance is unbiased for variance.) Xi+2...
2. (30 Points) X and Y ~ N (0,4) are two jointly Gaussian random variables, and E(XY) = 3 a. (10 Points) Find their joint PDF, f (x,y). b. (10 Points) Find the mean and variance of Z = X +Y. c. (10 Points) Find the mean and variance of Z = X + Y + 2.
question5 and the variance of the sample mean X? e 800, 25 800, 2.5 o 0,1 o 0,2.5 QUESTION 5 Let Xi, X., In be a random sample from a population that is distributed accordingly to a discrete mass function (r). Denote E(X)= ?, the popu- lation mean.Consider an estimator for the population mean-??? ax. where ??-lai-1. What is E(0)? e+1 0 QUESTION Let Yi. Y... , be a raudom sample from a popnlation that is normally ted with ulíknowli...
1. Consider a random experiment that has as an outcome the number x. Let the associated random variable be X, with true (population) and unknown probability density function fx(x), mean ux, and variance σχ2. Assume that n 2 independent, repeated trials of the random experiment are performed, resulting in the 2-sample of numerical outcomes x] and x2. Let estimate f x of true mean ux be μΧ-(X1 + x2)/2. Then the random variable associated with estimate Axis estimator Ax- (XI...
(7 points) Suppose X and Y are continuous random variables such that the pdf is f(x,y) xy with 0 sx s 1,0 s ys 1. a) Draw a graph that illustrates the domain of this pdf. b) Find the marginal pdfs of X and Y c) Compute μΧ, lly, σ' , σ' , Cov(X,Y),and ρ d) Determine the equation of the least squares regression line and draw it on your graph. (7 points) Suppose X and Y are continuous random...
Question 4 16 marks Let Y N(Hy, o). Then X := exp(Y) is said to be lognormally distributed with p.d.f. (In(x)-Hy) exp 202 fx(x) TOYV27 and denoted as LN(Hy, of). Let Xı,... , X, be random samples from the LN(Hy,of) distribution (a) Find the maximum likelihood estimator for ty, which we denote as fty (Hint: Use the fact that Yi In(X) is normally distributed with known mean and variance) Verify that the sought stationary point is a maximum (b) Verify...
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...
Please ignore part abc 4. Suppose that (X1, Yİ), , (XN,Yv) denotes a random sample. Let Si = a + bX, T, e+ dy, where a, b, c and d are constants. Let X ΣΧ, and σ2-NL Σ(x,-x)2, with the analogous expressions for y S, T. Let σΧΥ-ΝΤΣ (Xi-X)(X-Y), and let P:XY ƠXY/(ƠXƠY), with the analogous expressions for S, T. (a) Show that σ bbe (b) Show that ớsı, d ớx (c) Show that psT ST (d) How do the...
Parts e-h Suppose that (Xi,A), , (XN,Yv) denotes a random sample. Let Si = a+bX, T, = c+ dY,, where a, b, c and with the analogous expressions for Y, ST. Let σΧΥ ρΧΥ-Oxy/(ơxdY), with the analogous expressions for S, T Σ Xi, and σ. NLī Σί (Xi-X)2, -, Σ (Xi-X)(X-Y), and let d are constants. Let X = (a) Show that σ (b) Show that 37, b d ƠXY. (c) Show that ps- pxy. (d) How do the above...
3. Let X1, . . . , Xn be iid random variables with mean μ and variance σ2. Let X denote the sample mean and V-Σ,(X,-X)2 a) Derive the expected values of X and V b) Further suppose that Xi,...,Xn are normally distributed. Let Anxn - ((a) be an orthogonal matrix whose first row is (mVm Y = (y, . . . ,%), and X = (Xi, , Xn), are (column) vectors. (It is not necessary to know aij for...