R help - Feb 2002 - Managing Data [Summary]

A while ago I asked about data management approaches in R.  I was asked by
several people to post a summary of the responses and alas I am just getting
around to doing it.  I received several comments, both on and off list.
Below is a compilation of these responses.  Hope this is as helpful to
others as it was to me.

Best,

Brett


1.  Frank Harrell recommended a section, "Operating in S", from his
text
which can be found at:
  http://hesweb1.med.virginia.edu/biostat/s/doc/splus.pdf


2.  Jon Baron says that he does not use the files R stores at all, instead
following the procedures outlined in the beginning of his text:
  http://www.psych.upenn.edu/~baron/rpsych.htm

This approach involves "...involves keeping raw data in separate files,
each
with a name (supposedly a useful mnemonic), such as cba1.data, and scripts
in other separate files, such as cba1.R."  A script is written to read,
transform, manipulate, and analyze data.

Jim Lemon uses a similar approach but adds "Just to forestall any
confusion,
I noticed that [Jon Baron] didn't mention using read.table() or scan() in
the *.R file of commands to read in the data each time the script is run.
That way you never trash your data, and any data edits you do outside of R
are reflected in the next run of the script."


3. David Brahm offers another approach, a package he developed called g.data
available at:
  http://cran.us.r-project.org/src/contrib/PACKAGES.html#g.data

David says that this approach will be most intuitive to S-plus users.  The
package "...manages data in R in a manner very similar to the way S-Plus
does.  You assign 'permanent' objects to a particular position in your
search path (usually pos=2), then save all objects in that position with a
call to g.data.save()."



Brett A. Magill, Evaluation Associate
Research and Product Development
Health, Safety and Community Services
American Red Cross
magillb at usa.redcross.org


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The alternative I tend to use involves storing data in an external
database (in my case, PostgreSQL) and using a database driver (e.g.,
RPgSQL) to bring them in as needed.

Sorry to muddy the waters-
Andy

----------------------------------------------------------------------
Andrew J Perrin - andrew_perrin at unc.edu - http://www.unc.edu/~aperrin
 Assistant Professor of Sociology, U of North Carolina, Chapel Hill
      269 Hamilton Hall, CB#3210, Chapel Hill, NC 27599-3210 USA


On Mon, 25 Feb 2002, Magill, Brett wrote:
> A while ago I asked about data management approaches in R.  I was asked by
> several people to post a summary of the responses and alas I am just
getting
> around to doing it.  I received several comments, both on and off list.
> Below is a compilation of these responses.  Hope this is as helpful to
> others as it was to me.
> 
> Best,
> 
> Brett
> 
> 
> 1.  Frank Harrell recommended a section, "Operating in S", from
his text
> which can be found at:
>   http://hesweb1.med.virginia.edu/biostat/s/doc/splus.pdf
> 
> 
> 2.  Jon Baron says that he does not use the files R stores at all, instead
> following the procedures outlined in the beginning of his text:
>   http://www.psych.upenn.edu/~baron/rpsych.htm
> 
> This approach involves "...involves keeping raw data in separate
files, each
> with a name (supposedly a useful mnemonic), such as cba1.data, and scripts
> in other separate files, such as cba1.R."  A script is written to
read,
> transform, manipulate, and analyze data.
> 
> Jim Lemon uses a similar approach but adds "Just to forestall any
confusion,
> I noticed that [Jon Baron] didn't mention using read.table() or scan()
in
> the *.R file of commands to read in the data each time the script is run.
> That way you never trash your data, and any data edits you do outside of R
> are reflected in the next run of the script."
> 
> 
> 3. David Brahm offers another approach, a package he developed called
g.data
> available at:
>   http://cran.us.r-project.org/src/contrib/PACKAGES.html#g.data
> 
> David says that this approach will be most intuitive to S-plus users.  The
> package "...manages data in R in a manner very similar to the way
S-Plus
> does.  You assign 'permanent' objects to a particular position in
your
> search path (usually pos=2), then save all objects in that position with a
> call to g.data.save()."
> 
> 
> 
> Brett A. Magill, Evaluation Associate
> Research and Product Development
> Health, Safety and Community Services
> American Red Cross
> magillb at usa.redcross.org
> 
> 
>
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> r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
> Send "info", "help", or "[un]subscribe"
> (in the "body", not the subject !)  To: r-help-request at
stat.math.ethz.ch
>
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> 
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r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-help-request at
stat.math.ethz.ch
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