O: "Solving Chi Square Problems: E(s^2) and Var(s^2) Using MLE

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dim&dimmer
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Homework Statement


[tex]W = \frac{vS^2}{\sigma^2}[/tex], distributed as [tex]X^2_v[/tex]
Find [tex]E(s^2) and Var(s^2)[/tex]

Homework Equations


[tex]E(W) = v , Var(w)=2v[/tex]

The Attempt at a Solution


Have been trying to figure this out with no luck. Can I use MLE for variance to show [tex]Var(s^2)= \sigma^2[/tex]? Really don't know how to get started on this, any pointers would be appreciated.
DIM
 
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Remember that for any random variable [tex]X[/tex] and constant [tex]k[/tex]

[tex] E(kX) = kE(X), \quad Var(kX) = k^2 Var(X)[/tex]
 
Thank you,
Sheesh, should have posted my question ...days ago, pretty simple really.
Dimmer.