R help - Mar 2005 - LME correlation structures: user defined

Let me modify my question about user-defined covariance structures for LME
models: Can somebody tell me how I can see the code for the definition of the
correlation structures that come with the NLME package. Specifically I like to
see the code for the functions coef, corMatrix, and intialize for any of the
pre-defined correlation structures, and use this as a template to define a new
correlation structure. So how do I see e.g. the code for the method initialize
for the correlation structure corExp or corARMA?

thank you in advance!

Michael Jerosch-Herold

PS: Oh, and if somebody could still send me example code for a user defined
correlation structure I would much appreciate it, as my previous requests for
help have not yielded any response.

>Let me modify my question about user-defined covariance structures 
>for LME models: Can somebody tell me how I can see the code for the 
>definition of the correlation structures that come with the NLME 
>package. Specifically I like to see the code for the functions coef, 
>corMatrix, and intialize for any of the pre-defined correlation 
>structures, and use this as a template to define a new correlation 
>structure. So how do I see e.g. the code for the method initialize 
>for the correlation structure corExp or corARMA?
I'm interested in this too. Go to CRAN and download the source code 
for the nlme package. ungzip and untar it. Got to the R subdirectory. 
Inside that is a file called corStruct.R with all the method 
definitions for the built-in corStruct classes. Reading those should 
help.

Cheers,

Simon.

>
>thank you in advance!
>
>Michael Jerosch-Herold
>
>PS: Oh, and if somebody could still send me example code for a user 
>defined correlation structure I would much appreciate it, as my 
>previous requests for help have not yielded any response.
>
>______________________________________________
>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

-- 
Simon Blomberg, B.Sc.(Hons.), Ph.D, M.App.Stat.
Visiting Fellow
School of Botany & Zoology
The Australian National University
Canberra ACT 0200
Australia

T: +61 2 6125 8057  email: Simon.Blomberg at anu.edu.au
F: +61 2 6125 5573

CRICOS Provider # 00120C

Hi,

I noticed your old posts whilst tidying up my mailbox. I am struggling 
trying to understand the code to define new structures - part of the real 
work is hidden away in C code and I don't speak C very well. Have 
either of you successfully implemented any alternative structures? (At 
one stage I ws interested in trying Toeplitz forms, and now have a 
need for compound symmetry forms where the rho depends on a 
factor.) Have you anything beyond the source that might help? - for 
example a more richly commented example, or notes on what the C 
(and R)  functions actually do.

Regards,

Steve.




Date sent:      	Wed, 23 Mar 2005 10:56:46 +1100
To:             	"Michael Jerosch-Herold" <jeroschh at
ohsu.edu>, R-help at stat.math.ethz.ch
From:           	Simon Blomberg <Simon.Blomberg at anu.edu.au>
Subject:        	Re: [R] LME correlation structures: user defined
Copies to:      	
> >Let me modify my question about user-defined covariance structures
> >for LME models: Can somebody tell me how I can see the code for the
> >definition of the correlation structures that come with the NLME
> >package. Specifically I like to see the code for the functions coef,
> >corMatrix, and intialize for any of the pre-defined correlation
> >structures, and use this as a template to define a new correlation
> >structure. So how do I see e.g. the code for the method initialize
> >for the correlation structure corExp or corARMA?
> 
> I'm interested in this too. Go to CRAN and download the source code
> for the nlme package. ungzip and untar it. Got to the R subdirectory.
> Inside that is a file called corStruct.R with all the method
> definitions for the built-in corStruct classes. Reading those should
> help.
> 
> Cheers,
> 
> Simon.
> 
> 
> >
> >thank you in advance!
> >
> >Michael Jerosch-Herold
> >
> >PS: Oh, and if somebody could still send me example code for a user
> >defined correlation structure I would much appreciate it, as my
> >previous requests for help have not yielded any response.
> >
> >______________________________________________
> >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
> 
> 
> -- 
> Simon Blomberg, B.Sc.(Hons.), Ph.D, M.App.Stat.
> Visiting Fellow
> School of Botany & Zoology
> The Australian National University
> Canberra ACT 0200
> Australia
> 
> T: +61 2 6125 8057  email: Simon.Blomberg at anu.edu.au
> F: +61 2 6125 5573
> 
> CRICOS Provider # 00120C
> 
> ______________________________________________
> 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

  Dr Steve Roberts 
  steve.roberts at manchester.ac.uk

Senior Lecturer in Medical Statistics,
CMMCH NHS Trust and University of Manchester Biostatistics Group,
0161 275 5192/5764 / 0161 276 5785