maybe another way is by reconstructing the formula using paste(), e.g.,
data <- data.frame(y = rnorm(5), x1 = runif(5),
z = runif(5), age = runif(5))
nameRsp <- "y"
nams <- names(data)
namsX <- nams[!nams %in% nameRsp]
form <- as.formula(paste(nameRsp, "~" ,
paste("log(", namsX, ")", sep = "", collapse = "+")))
lm(form, data)
I hope it helps.
Best,
Dimitris
On 6/18/2011 10:41 AM, Dennis Murphy wrote:
Yes, it's possible, but if you want to do prediction on future
x-values, you will likely have a problem.
One way to do it would be something like (assuming y is the first column of dat)
reg<- lm(y ~ log(as.matrix(dat[, -1])), dat)
but the output would be pretty ugly (see summary(reg)). Another would
be to construct the matrix outside the data frame and do something
like
X<- log(as.matrix(dat[, -1]))
reg<- lm(dat$y ~ X)
There may be better ways, though...
Dennis
On Fri, Jun 17, 2011 at 11:08 PM, Scott Fortmann-Roe<scot...@gmail.com> wrote:
Hi,
I would like to do a regression like:
reg<- lm(y~log(.), data)
where the log function is applied to "." in the form:
log(x1)+ log(x2)+ log(x3)...
instead of in the form
log(x1+x2+x3+...)
Is this possible?
Thank you,
Scott
[[alternative HTML version deleted]]
______________________________________________
R-help@r-project.org 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.
______________________________________________
R-help@r-project.org 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.
--
Dimitris Rizopoulos
Assistant Professor
Department of Biostatistics
Erasmus University Medical Center
Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands
Tel: +31/(0)10/7043478
Fax: +31/(0)10/7043014
Web: http://www.erasmusmc.nl/biostatistiek/
______________________________________________
R-help@r-project.org 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.
