R citation which year to cite?

Question

Most of the time my R version and packages are reasonably up to date. Now I wonder what year to cite when using citation("somepackage"). Basically all packages are 2012 then. How can I find out the real date when they first came up? Or should I really cite the most recent version?

Answer 1

The norm in the medical field seems to be to cite something like this in the text:

We used Stata version 9.2 (Stata Corporation, East Nowhere, Texas, 2006).

That norm argues for citing the year of the version you actually used. And, in my view it makes sense if you want subsequent authors to be able to replicate your results.

There's a whole emerging field that's trying to figure out how to cite things other than papers (see, for example Heather Piwowar's work). If there's a Journal of Statistical Software article on the R version you want (more likely for packages than for base R), you could cite that. Or cite the R Journal's updates for the relevant version.

Answer 2

Why doesn't anybody mention the obvious? There is a citation() command in R itself:

edd@max:~$ R --silent -e 'citation()'
R> citation()

To cite R in publications use:

  R Core Team (2012). R: A language and environment for statistical computing. 
  R Foundation for Statistical Computing, Vienna, Austria.
  ISBN 3-900051-07-0, URL http://www.R-project.org/.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {R: A Language and Environment for Statistical Computing},
    author = {{R Core Team}},
    organization = {R Foundation for Statistical Computing},
    address = {Vienna, Austria},
    year = {2012},
    note = {{ISBN} 3-900051-07-0},
    url = {http://www.R-project.org/},
  }

We have invested a lot of time and effort in creating R, please cite it 
when using it for data analysis. See also ‘citation("pkgname")’ for citing 
R packages.

R> 
R> 
edd@max:~$