On Tue, 13 Mar 2007 14:15:16 -0400,
"Bos, Roger" <[EMAIL PROTECTED]> wrote:
> I'm curious what this transformation does, but I am not curious enough
> to pay $14 to find out. Someone once told me that the arcsine was a
> good way to transform data and make it more 'normal'. I am wondering if
> this is an improved method. Anyone know of a free reference?
My Zar¹, says this is just:
p' = 1/2 * (asin(sqrt(x / (n + 1))) + asin(sqrt((x + 1) / (n + 1))))
so solving for x should give the back-transformation. It is recommended
when the proportions that need to be "disciplined" are very close to the
ends of the range (0, 1; 0, 100).
+---- *Footnotes* ----+
¹ @BOOK{149,
title = {Biostatistical analysis},
publisher = {Prentice-Hall, Inc.},
year = {1996},
author = {Zar, J. H.},
address = {Upper Saddle River, New Jersey},
key = {149},
}
--
Seb
______________________________________________
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
