the discrete prob distribution(adsbygoogle = window.adsbygoogle || []).push({});

X/Y - G - D

0 - 0,1 - 0,15

1 - 0,1 - 0,3

2 - 0,05 - 0,3

this is what i have so far:

E[X|Y=D]=0,2

E[X|Y=g]=0,9

E[X]=0,725

E[X^2|Y=D]=0,3

E[X^2|Y=G]=1,5

Var(X|Y=G)=0,69

Var(X|Y=D)=0,26

i.e. [X]=0,2*0,25 + 0,9*0,75=0,725

is the previous correct and how do i find Var(X)?

the conditional variance forumal is:

Var(X)=E[Var(X|Y)] + Var(E[X|Y])

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# Homework Help: Finding conditional variance?

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