Re: Practice Exam Question 59

AMFMPIP@aol.com
Wed, 28 Apr 1999 10:28:07 EDT

I think that the question meant to ask for Woll's 1st formula, not Finger's.
That formula is Var(M) = Var(X)-E(X)

E(X)= ((126*1)+(52*2))/903 = .255

Var (X) = E(X^2)-(E(X)^2)

E(X^2)= ((126*1)+(52*4))/903 = .370

Var(X)=.370 - (.255)^2 = .305

Var(M)= .305 - .255 = .05

However, I think the coefficient of variation^2 should be
(Var(M))/(E(M)^2) = (.305)/(.255)^2 = 2.166

Efficiency = 2.166/(1.1)^2 = 1.79

Since I just figured out the Woll formulas a couple of days ago and am not
positive, I hope that this is correct.

Faith