Re: [R] Pre-model Variable Reduction

2008-12-09 Thread Mark Difford
t;> >>> Ravi Varadhan, Ph.D. >>> >>> Assistant Professor, The Center on Aging and Health >>> >>> Division of Geriatric Medicine and Gerontology >>> >>> Johns Hopkins University >>> >>> Ph: (410) 502-2619 >

Re: [R] Pre-model Variable Reduction

2008-12-09 Thread Frank E Harrell Jr
w.jhsph.edu/agingandhealth/People/Faculty/Varadhan.html -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gabor Grothendieck Sent: Tuesday, December 09, 2008 8:00 AM To: Harsh Cc: r-help@r-project.org Subject: Re: [R] Pre-model Variable Reduction See: ?prcomp ?

Re: [R] Pre-model Variable Reduction

2008-12-09 Thread Mark Difford
lty/Varadhan.html > > > > > > > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > On > Behalf Of Gabor Grothendieck > Sent: Tuesday, December 09, 20

Re: [R] Pre-model Variable Reduction

2008-12-09 Thread Harsh
Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of Gabor Grothendieck > Sent: Tuesday, December 09, 2008 8:00 AM > To: Harsh > Cc: r-help@r-project.org > Subject: Re: [R] Pre-model Variable Reduction > > See: > > ?prcomp > ?princomp

Re: [R] Pre-model Variable Reduction

2008-12-09 Thread Ravi Varadhan
PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gabor Grothendieck Sent: Tuesday, December 09, 2008 8:00 AM To: Harsh Cc: r-help@r-project.org Subject: Re: [R] Pre-model Variable Reduction See: ?prcomp ?princomp On Tue, Dec 9, 2008 at 5:34 AM, Harsh <[EMAIL PROTECTED]> wrote: > Hello All, &

Re: [R] Pre-model Variable Reduction

2008-12-09 Thread Frank E Harrell Jr
Harsh wrote: Hello All, I am trying to carry out variable reduction. I do not have information about the dependent variable, and have only the X variables as it were. In selecting variables I wish to keep, I have considered the following criteria. 1) Percentage of missing value in each column/var

Re: [R] Pre-model Variable Reduction

2008-12-09 Thread Gabor Grothendieck
See: ?prcomp ?princomp On Tue, Dec 9, 2008 at 5:34 AM, Harsh <[EMAIL PROTECTED]> wrote: > Hello All, > I am trying to carry out variable reduction. I do not have information > about the dependent variable, and have only the X variables as it > were. > In selecting variables I wish to keep, I have

Re: [R] Pre-model Variable Reduction

2008-12-09 Thread Mark Difford
Hi Harsh, >> I looked for other R packages that allow me to do variable reduction >> without considering a dependent variable. Have look at package subselect. This has an implementation of the genetic algorithm, along with some other methods. It should do what you want. Regards, Mark. Harsh-

Re: [R] Pre-model Variable Reduction

2008-12-09 Thread Hans W. Borchers
Harsh gmail.com> writes: > > Hello All, > I am trying to carry out variable reduction. I do not have information > about the dependent variable, and have only the X variables as it > were. > ... > I looked for other R packages that allow me to do variable reduction > without considering a depend

[R] Pre-model Variable Reduction

2008-12-09 Thread Harsh
Hello All, I am trying to carry out variable reduction. I do not have information about the dependent variable, and have only the X variables as it were. In selecting variables I wish to keep, I have considered the following criteria. 1) Percentage of missing value in each column/variable 2) Varian