Hi all,
I am running R version 2.4.0 on Windows XP. I am new and have the following question:
I have a dataset of columns named x1, x2, x3...xn. I would like to write a linear regression using lm that looks like this:
lm(y~x1+x2+x3+...+xn)
If I try to use the following code, I only get the model for y~x1+xn:
n<-ncol(dataset)
model<-lm(y~x1)
for(i in 1:n) {
model.new<-update(model, .~.+dataset[,i])
}
The purpose of this is so I can use stepAIC with model.new as the upper scope and model as the lower.
I know there must be a simple way to do this, but I am not yet familiar with much syntax. Any help appreciated!
--
Brooke LaFlamme
Cornell University
Adding terms to a function
3 messages · Brooke LaFlamme, Simon Blomberg, Gabor Grothendieck
How about this:
form <- formula(paste("y ~", paste("x", 1:n, sep="", collapse=" + ")))
model <- lm(form)
HTH,
Simon.
Brooke LaFlamme wrote:
Hi all,
I am running R version 2.4.0 on Windows XP. I am new and have the following question:
I have a dataset of columns named x1, x2, x3...xn. I would like to write a linear regression using lm that looks like this:
lm(y~x1+x2+x3+...+xn)
If I try to use the following code, I only get the model for y~x1+xn:
n<-ncol(dataset)
model<-lm(y~x1)
for(i in 1:n) {
model.new<-update(model, .~.+dataset[,i])
}
The purpose of this is so I can use stepAIC with model.new as the upper scope and model as the lower.
I know there must be a simple way to do this, but I am not yet familiar with much syntax. Any help appreciated!
--
Brooke LaFlamme
Cornell University
______________________________________________ R-help at 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.
Simon Blomberg, B.Sc.(Hons.), Ph.D, M.App.Stat. Centre for Resource and Environmental Studies The Australian National University Canberra ACT 0200 Australia T: +61 2 6125 7800 email: Simon.Blomberg_at_anu.edu.au F: +61 2 6125 0757 CRICOS Provider # 00120C The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data. - John Tukey.
Using the builtin anscombe data set try this where we note that the first 4 columns are x1, ..., x4 and the fifth column is y1. for(i in 1:4) print(coef(lm(y1 ~., anscombe[c(1:i, 5)])))
On 12/6/06, Brooke LaFlamme <bal44 at cornell.edu> wrote:
Hi all,
I am running R version 2.4.0 on Windows XP. I am new and have the following question:
I have a dataset of columns named x1, x2, x3...xn. I would like to write a linear regression using lm that looks like this:
lm(y~x1+x2+x3+...+xn)
If I try to use the following code, I only get the model for y~x1+xn:
n<-ncol(dataset)
model<-lm(y~x1)
for(i in 1:n) {
model.new<-update(model, .~.+dataset[,i])
}
The purpose of this is so I can use stepAIC with model.new as the upper scope and model as the lower.
I know there must be a simple way to do this, but I am not yet familiar with much syntax. Any help appreciated!
--
Brooke LaFlamme
Cornell University
______________________________________________ R-help at 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.