Exercises1. Suppose that X1 and X2 are random variables with zero mean and unitvariance. If the correlation coefficient of X1 and X2 is –0.5, then what is thevariance of Y = =k2Xk ?Lk=12. If the joint density of the random variables X and Y isif (x, y) E { (x,0), (0, -y)|x, y = -2, –1, 1,2}f(x, y)otherwise,3. Suthe random variables X and Y are indelent and identicallydistributed. Let Z = aX +Y. If the correlation coefficient between X andZ is , then what is the value of the constant a ?

Answered: 1. Suppose that X1 and X2 are random…

1. Suppose that X1 and X2 are random variables with zero mean and unit variance. If the correlation coefficient of X1 and X2 is -0.5, then what is the variance of Y =E-k² Xk ? k%3D1

Algebra & Trigonometry with Analytic Geometry

13th Edition

ISBN:9781133382119

Author:Swokowski

Publisher:Swokowski

Chapter10: Sequences, Series, And Probability

Section10.8: Probability

Problem 32E

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Exercises
1. Suppose that X1 and X2 are random variables with zero mean and unit
variance. If the correlation coefficient of X1 and X2 is –0.5, then what is the
variance of Y = =k2Xk ?
Lk=1
2. If the joint density of the random variables X and Y is
if (x, y) E { (x,0), (0, -y)|x, y = -2, –1, 1,2}
f(x, y)
otherwise,
3. Su
the random variables X and Y are inde
lent and identically
distributed. Let Z = aX +Y. If the correlation coefficient between X and
Z is , then what is the value of the constant a ?

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