Solution Found!
Show that the result given in Exercise 3.158 also holds
Chapter 4, Problem 137E(choose chapter or problem)
Problem 137E
Show that the result given in Exercise 3.158 also holds for continuous random variables. That is, show that, if Y is a random variable with moment-generating function m(t) and U is given by U = aY + b, the moment-generating function of U is etbm(at). If Y has mean μ and variance σ 2, use the moment-generating function of U to derive the mean and variance of U .
Reference
If Y is a random variable with moment-generating function m(t) and if W is given by W = aY + b, show that the moment-generating function of W is etbm(at).
Questions & Answers
QUESTION:
Problem 137E
Show that the result given in Exercise 3.158 also holds for continuous random variables. That is, show that, if Y is a random variable with moment-generating function m(t) and U is given by U = aY + b, the moment-generating function of U is etbm(at). If Y has mean μ and variance σ 2, use the moment-generating function of U to derive the mean and variance of U .
Reference
If Y is a random variable with moment-generating function m(t) and if W is given by W = aY + b, show that the moment-generating function of W is etbm(at).
ANSWER:
Solution 137E
Step1 of 2:
Let us consider a random variable Y it has mean and variance . If Y is a random variable with moment-generating function m(t).
Also we have U = aY + b.
We need to find the moment generating function of U and also we need to derive mean and variance of U.
Step2 of 3:
Let,
Substitute U value in above equation we get,
Therefore moment generating function of U is .