If Var(Y) = σ², what is Var(Y²)?

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If Var(Y)=[tex]\sigma^2[/tex], then Var ( Y2 ) = ?
 
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[tex]vary(Y^2) = E(Y^4) - E(Y^2) [/tex]

(same basic patten for the random variable [tex]Y^2[/tex] as for any other random variable).
 


statdad said:
[tex]vary(Y^2) = E(Y^4) - E(Y^2) [/tex]

(same basic patten for the random variable [tex]Y^2[/tex] as for any other random variable).
should be
[tex]vary(Y^2) = E(Y^4) - (E(Y^2))^2 [/tex]
 


Crap - yes, mathman is correct. Time to stop posting for a while.
 

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