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enaj
10-24-2008, 01:00 PM
Can anyone tell me what the VHM and EVPV are equivalent to? I know the formulas are:

EVPV = E[Var(X|Y)]
VHM = Var[E(X|Y)]

In 2001 #30, it appears that

EVPV = E[Var(X / Y) * Y^2]
VHM = Var[E(X / Y)*Y]

I'm not sure how these two forms are equal. I'd appreciate anyone's input on this.

DOT
10-24-2008, 01:21 PM
Can anyone tell me what the VHM and EVPV are equivalent to? I know the formulas are:

EVPV = E[Var(X|Y)]
VHM = Var[E(X|Y)]

In 2001 #30, it appears that

EVPV = E[Var(X / Y) * Y^2]
VHM = Var[E(X / Y)*Y]

I'm not sure how these two forms are equal. I'd appreciate anyone's input on this.

EVPV = E[Var(X|Y)] = E[Var(d*Y|Y)] = E[(Y^2)]*Var(d) = {E[Y^2] + E[Y]^2}*Var(d)

VHM = Var[E(X|Y)] = Var[E(dY|Y)] = (d^2)*Var(Y)

d = X/Y

Five in Two
10-24-2008, 02:05 PM
I'm guessing you never took exam 4/C?

intelmic
10-24-2008, 02:31 PM
I was *the king* at VHM, EPV when I took C. But it seems like such a long time ago... I even struggled when I first read Brosius.

SoCalChavo
10-25-2008, 02:37 PM
EVPV = E[Var(X|Y)] = E[Var(d*Y|Y)] = E[(Y^2)]*Var(d) = {E[Y^2] + E[Y]^2}*Var(d)

VHM = Var[E(X|Y)] = Var[E(dY|Y)] = (d^2)*Var(Y)

d = X/Y

The formula for the EVPV should finish as:
{VAR[Y] + E[Y]^2}*Var(d) not {E[Y^2] + E[Y]^2}*Var(d)

DOT
10-25-2008, 03:07 PM
The formula for the EVPV should finish as:
{VAR[Y] + E[Y]^2}*Var(d) not {E[Y^2] + E[Y]^2}*Var(d)