Thread: Simple Variance Question
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Old 03-21-2007, 06:19 PM
djames djames is offline
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Default Re: Simple Variance Question
V(x) = E(x^2) - E(x)^2

For the case of the die,
E(x) = 3.5
E(x)^2 = 12.25
E(x^2) = 15.16667
V(x) = 2.91667

Coin flip (where 0 is one side, 1 is the other)
E(x) = E(x^2) = 0.5
V(x) = 0.25
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