Dear all,
I guess I am doing something wrong.
I am trying to apply a formula for sample size calculation as in the book
"Design and Analysis of Clinical Trials", from Chow et all.
There a suggested sample size strategy uses the formula
0.30/0.45=F(0.80,2n,2n)/F(0.025,2n,2n)
which gives n=96.
(here F(alfa,k,n) is the upper (alfa)th quantile of an F distribution with
k,n degrees of freedom)
I have been trying to get n=96 using the following code in SAS.
data l;
do n=1 to 200;
val=quantile('F',0.8,2*n,2*n)/quantile('F',0.025,2*n,2*n);
output;
end;
run;
but val doesnot get any close to 0.30/0.45.
Thank you,
Manuel
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