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10 questions from this quiz
A value that can take only certain fixed values
Its value depends on chance
List/formula of outcomes & probabilities
The actual outcome
E(X)=ΣxpE(X) = \Sigma xpE(X)=Σxp
Mean score per turn
E(X2)=Σx2pE(X^2) = \Sigma x^2pE(X2)=Σx2p
Var(X)=E(X2)−[E(X)]2\text{Var}(X) = E(X^2) - [E(X)]^2Var(X)=E(X2)−[E(X)]2
s2s^2s2
s2=nn−1σ2s^2 = \frac{n}{n-1}\sigma^2s2=n−1nσ2
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