Message-ID: <x28yk2cgc1.fsf@biostat.ku.dk>
Date: 2004-01-21T00:09:50Z
From: Peter Dalgaard
Subject: Combining several regressions
In-Reply-To: <400DBDA7.8050009@auckland.ac.nz>
Hadley Wickham <h.wickham at auckland.ac.nz> writes:
> For example, I want to fit separate loess regressions for each value
> of some conditioning value. I can do the regressions with
> by(data.frame, conditioning.variable, function(subset) { loess(y ~ x,
> subset) }) but I'm at a loss as how to get the fitted values out and
> match them up with the rows in the original dataset.
> Any suggestions?
[Untested!]
b <- by(data.frame, conditioning.variable,
function(subset) { loess(y ~ x, subset) })
unsplit(lapply(b,fitted), conditioning.variable)
You might need to replace the by() by an
lapply(split(data.frame,cond.var), FUN)
construction, but it doesn't look like it should be necessary.
--
O__ ---- Peter Dalgaard Blegdamsvej 3
c/ /'_ --- Dept. of Biostatistics 2200 Cph. N
(*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk) FAX: (+45) 35327907