- #1
grimster
- 39
- 0
the discrete prob distribution
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])
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])