of lambda to use then you can use the bct
function from TeachingDemos (or other ways) to compute the transformed y values.
Hope this helps,
-Original Message-
From: [EMAIL PROTECTED] on behalf of Torsten Mathies
Sent: Sat 7/29/2006 12:52 AM
To: r-help@stat.math.ethz.ch
Subject: [R] boxcox
I've got a vector of data (hours to drive from a to b) y.
After a qqplot I know, that they don't fit the normal probability.
I would like to transform these data with the boxcox transformation
(MASS), that they fit the model.
When I try
ybx-boxcox(y~1,0)
qqnorm(ybx)
the plot is
Dear r-helpers,
Prior to analysis of variance, I ran the Boxcox function (MASS library) to
find the best power transformation of my data. However, reading the Boxcox
help file, I cannot figure out if this function (through its associated
log-likelihood function) corrects for * normality only *
Please consult the reference on the help page of that function: it _is_
support software for a book. It implements the Box-Cox procedure (as it
says). The original Box-Cox paper has three aims, two of which you have
mentioned (but perhaps the most inportant one is the one you
have not
