Find directly the expected value and the variance of :
Recall that xi ....xn are assumed to be non random and that , with
Find directly the expected value and the variance of : Recall that xi ....xn are assumed...
3. Let Xi, . . . , Xn be iid randoln 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,-.,X, are normally distributed. Let Anxn ((a)) an orthogonal matrix whose first rOw 1S be , ..*) and iet Y = AX, where Y (Yİ, ,%), ard X-(XI, , X.), are (column) vectors. (It is not necessary to know aij...
Readings: Review for the 5 properties of expected value and variance e iid. Recall that ii.d. stands for independent and identically distributed.) Since have the same expected value and variance. Le 5. Let X,... Xn, b 1. ..., Xn all have the same distributi E(X1)-: μ and Var(X1) σ. Find the following in terms of μ and σ. (a) E(X). Note this is not pH (b) E0%XYn). (c) Now, define W by Find E(W) and Var(W).
Let Xi, , Xn be a random sample from a n(o, σ*) distribution with pdf given by 2πσ I. Is the distribution family {f(x; σ), σ 0} complete? 2. Is PCH)〈1) the same for all σ ? 3. Find a sufficient statistic for σ. 4. Is the sufficient statistic from (c) also complete!? Let Xi, , Xn be a random sample from a n(o, σ*) distribution with pdf given by 2πσ I. Is the distribution family {f(x; σ), σ 0}...
We have a dataset with n = 10 pairs of observations (xi; yi), and Xn i=1 xi = 683; Xn i=1 yi = 813; Xn i=1 x2i = 47; 405; Xn i=1 xiyi = 56; 089; Xn i=1 y2 i = 66; 731: What is an approximate 99% confidence interval for the intercept of the line of best fit? We have a dataset with n= 10 pairs of observations (ri, Yi), and n n Σ Xi = 683, 2 yi...
Xn are independent normal variates with the same variance σ, but with Suppose that Xi, X2, different means, Xi ~N(pbi,ơ2), for i-1.2, n where bi, b,.. k constants. (a) Find expressions for the MLE of μ and σ. You need not show the second derivative conditions (b) Suppose that b,-b2-...-bn. Find a simplified expression for the MLE of μ (c) Suppose that b,-b2-...-bn-1, and , is known. Find the MLE ofơ
3. [6 pts] Let Xi, . . . , Xn be a random sample from a distribution with variance σ2 < oo. Find cov(X,-x,x) for i 1,..,n. 3. [6 pts] Let Xi, . . . , Xn be a random sample from a distribution with variance σ2
We have a dataset with n = 10 pairs of observations (xi; yi), and Xn i=1 xi = 683; Xn i=1 yi = 813; Xn i=1 x2i = 47; 405; Xn i=1 xiyi = 56; 089; Xn i=1 y2 i = 66; 731: What is the coefficient of correlation for this data? We have a dataset with n= 10 pairs of observations (li, yi), and n n Σ ti = 683, Σ9: = 813, i=1 η α? = 47, 405,...
5. Let X1,X2, . , Xn be a random sample from a distribution with finite variance. Show that (i) COV(Xi-X, X )-0 f ) ρ (Xi-XX,-X)--n-1, 1 # J, 1,,-1, , n. OV&.for any two random variables X and Y) or each 1, and (11 CoV(X,Y) var(x)var(y) (Recall that p vararo 5. Let X1,X2, . , Xn be a random sample from a distribution with finite variance. Show that (i) COV(Xi-X, X )-0 f ) ρ (Xi-XX,-X)--n-1, 1 # J,...
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...
We have a dataset with n = 10 pairs of observations (xi; yi), and Xn i=1 xi = 683; Xn i=1 yi = 813; Xn i=1 x2i = 47; 405; Xn i=1 xiyi = 56; 089; Xn i=1 y2 i = 66; 731: What is an approximate 95% confidence interval for the mean response at x0 = 90? We have a dataset with n = 10 pairs of observations (li, Yi), and n n Σ Xi = 683, Yi =...