Learn How to Calculate Var(Y) and Var(Y2) with Statistics Equation Help"

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Discussion Overview

The discussion focuses on calculating the variance of the random variable Y squared, Var(Y²), and how it relates to the variance of Y, Var(Y). Participants explore the statistical equations involved in these calculations.

Discussion Character

  • Technical explanation

Main Points Raised

  • One participant asks for the calculation of Var(Y²) given that Var(Y) = σ².
  • Another participant proposes that Var(Y²) = E(Y⁴) - E(Y²).
  • A third participant corrects the previous claim, stating that Var(Y²) should actually be Var(Y²) = E(Y⁴) - (E(Y²))².
  • A later reply acknowledges the correction and expresses a desire to refrain from further posting.

Areas of Agreement / Disagreement

There is disagreement regarding the correct formula for Var(Y²), with different participants proposing different equations. The discussion remains unresolved as to which formula is correct.

DavidLiew
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If Var(Y)=[tex]\sigma^2[/tex], then Var ( Y2 ) = ?
 
Last edited:
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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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