Re: Jack WRONG

Jack wrote:


*** The theoretical formulas for m = 7 degrees of
freedom and the r = -1 moment are

E(w) = (2/m)^(r/2)*Gamma((m+r)/2)/Gamma(m/2)
w(0.95) = 1/sqrt(chi(m; 0.05)/m))

Substituting m = 7 and r = -1, we obtain,

E(w) = 1.126
w(0.95) = 1.797

Jack ***

WRONG

____E(w) = 1.199 *

____licas (Luis A. Afonso)

* I obtained in a new attempt (cft. 1.200 I
posted)

____licas (Luis A. Afonso)


Luis, how would you change the equation for the mean
of 1/s?

Even using simulations rather than the exact formula,
ten runs of 1000 w's by Excel come up with average
w's of 1.1311, 1.1236, 1.1300, 1.1252, 1.1259,
1.1211, 1.1188, 1.1263, 1.1252, and 1.1219. This
averages out to 1.125.

Jack


My apologies. I thought from your notation that w was the ratio of the population standard deviation to the sample standard deviation.

Jack
.

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