SupposeX1,...,Xn are independent random samples from a population distributed as N(μ1,σ21) andY1,...,Ym are a independent random samples from N(μ2,σ22). Suppose further that Xi‘s and Yj‘s are independent for any i=1,...,n and j= 1,...,m.a. Determine E[ ̄X+ ̄Y]. b.Determine Var [ ̄X+ ̄Y]. c.What is the distribution of ̄X+ ̄Y?
SupposeX1,...,Xn are independent random samples from a population distributed as N(μ1,σ21) andY1,...,Ym are a independent random...
Let X1 and X2 be independent random variables with means μ1 and μ2, and variances σ21 and σ22, respectively. Find the correlation of X1 and X1 + X2. Note that: The covariance of random variables X; Y is dened by Cov(X; Y ) = E[(X - E(X))(Y - E(Y ))]. The correlation of X; Y is dened by Corr(X; Y ) =Cov(X; Y ) / √ Var(X)Var(Y )
Find the standardized test statistic, t, to test the claim that μ1 < μ2. Two samples are random, independent, and come from populations that are normally distributed. The sample statistics are given below. Assume that two populations' variance is the same (σ21= σ22). n1 = 15 n2 = 15 x1 = 25.76 x2 = 28.31 s1 = 2.9 s2 = 2.8
Suppose that independent samples of sizes n1, n2, . . . , nk are taken from each of k normally distributed populations with means μ1,μ2, . . . , μk and common variances, all equal to σ 2. Let Yi j denote the j th observation from population i, for j = 1, 2, . . . , ni and i = 1, 2, . . . , k, and let n = n1 + n2 + ··· + nk...
Let X1,..., Xn and Yi,..., Ym be two independent samples from a Poisson dis- tribution with parameter X. Let a, b be two positive numbers. Consider the following estimator for A: Y1 X1 Xn . Ym b n m (a) What condition is needed on a and b so that X is unbiased? (b) What is the MSE of A?
Let X1, ..., Xn and Y1, ..., Ym be two independent samples from a Poisson dis- tribution with parameter 1. Let a, b be two positive numbers. Consider the following estimator for 1: i ,Y1 +...+Ym = a- X1 +...+Xn n т (a) What condition is needed on a and b so that û is unbiased? (b) What is the MSE of i?
1. You have two independent samples, X1,... , Xn and Y,... , Ym drawn from populations with continuous distributions. Suppose the two samples are combined and the combined set of values are put in increasing order. Let Vr-1 if the value with rank r in the combined sample is a Y and V0 if it is an X, for r-1...., N, where N-m+n Show that, if the two populations are the same then mn The general linear rank statistic is...
Given two independent random samples X1, ..., Xn and Y1, ..., Ym with normal dis- tributions N(Hz, o?) and N(Hy, oz), determine a generalized likelihood ratio test for Ho : Mix - My = 0 versus H : plz – My 70 at a given significance level a (01, 0y unknown but equal).
2. Suppose that {X1, ..., Xn} are independent and identically distributed random variables from a distribution with p.d.f. See-ox if x > 0 f(x) = 10 if x = 0 Let Y = min <i<n X;. Find the p.d.f. of Y.
2. Suppose that X1, X2, ..., Xn " N(41,01) and Yı,Y2,...,Ym * N(H2;02) are two independent random samples. (a) What is E[X - Ÿ]? (b) Find a general expression for Var[X – Ý), and use this to find an expression for the standard error ox-ý = StDev(X – Ỹ). (c) Suppose that of = 2 and o = 2.5, and also that n = 10 and m = 15. Determine the probability P(|X – Ý - (µ1 – 42)| <...
Let X1, ..., Xn and Y1, ...,Ym be two independent samples from a Poisson dis- tribution with parameter 1. Let a,b be two positive numbers. Consider the following estimator for 1: i-X1 + ... + Xn+hY1 + ... + Ym m п (a) What condition is needed on a and b so that û is unbiased? (b) What is the MSE of Î?