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Cara Wales English 2 cards

Cards in this deck (2)

1Chapter 14 - Expectation For any random variables X and Y and any constants a and b: Var(aX+bY)=? Cov(aX+bY,cX+dY)=? Cov(X+Y,Z)=? Cov(SIGMAaiXi,SIGMAbjYj)a^2Var(X)+2abCov(X,Y)+b^2Var(Y)
acVar(X)+bdVar(Y)+(ad+bc)Cov(X,Y)
Cov(X,Z)+Cov(Y,Z)
SIGMAi=1SIGMAj=1[aibjCov(Xi,Yj)
2Chapter 14 - Conditional Expectation For any random variable X and Y the following hold: E[X¦Y=y]=? Ey(E[X¦Y])=? E[Y¦X=x]=? Ex(E[Y¦X])=?integral[x] xfx¦Y=y(x¦y)dx
E(X)
integral[y] yfy¦X=x(y¦x)dy
E(Y)