Let X, Y, and Z be random variables, and let Cov(:,-) denote the covariance operator as usual. Suppose that the variance of X is 0.7,Cov(X,Y) = 0.4, Cov(X,Z) = 1.2, and Cov(Y,Z) = 0.8. Find each of the following to two decimal places.(a) Cov(11Y, 4X) (b) Cov(11Y + 3, 4X + 8Z)

We want to find (1) Cov(11Y,4X)= ? (2)Cov(11Y+3, 4X+8Y)= ?

Answered: Let X, Y, and Z be random variables,…

Calculus For The Life Sciences

2nd Edition

ISBN:9780321964038

Author:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.

Publisher:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.

Chapter1: Functions

Section1.2: The Least Square Line

Problem 1E

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Let X, Y, and Z be random variables, and let Cov(,) denote the covariance operator as usual. Suppose that the variance of X is 0.7, Cov(X,Y) = 0.4, Cov(X,Z) = 1.2, and Cov(Y,Z) = 0.8. Find each of the following to two decimal places. a) Cov(11Y, 4X)