Message-ID: <2110151104.4193991241612533094.JavaMail.root@spooler8-g27.priv.proxad.net>
Date: 2009-05-06T12:22:13Z
From: xavier.chardon at free.fr
Subject: model fitting using by(): how to get fitted values?
In-Reply-To: <1584264237.4193871241612510312.JavaMail.root@spooler8-g27.priv.proxad.net>
Hi all,
I'm doing nonlinear regressions on data with several factors. I want to fit say a logistic curve with different parameter values for each factor level. So I'm doing something like:
tmp <- by( myData, list(myFactor1, myFactor2), function(x) nls(...) )
It works fine. However, I could not find an easy way to retrieve fitted values. I can use fitted() on each element of tmp, but that gives me as many vectors as there are combinations of factor levels.
I was thinking of using by() again, but I can't figure out how to write it properly.
Any ideas?
Thanks a lot,
Xavier