Who Did What? The Roles of R Package Authors and How to Refer to Them

Computational infrastructure for representing persons and citations has been available in R for several years, but has been restructured through enhanced classes "person" and "bibentry" in recent versions of R. The new features include support for the specification of the roles of package authors (e.g. maintainer, author, contributor, translator, etc.) and more flexible formatting/printing tools among various other improvements. Here, we introduce the new classes and their methods and indicate how this functionality is employed in the management of R packages. Specifically, we show how the authors of R packages can be specified along with their roles in package ‘DESCRIPTION’ and/or ‘CITATION’ files and the citations produced from it. R packages are the result of scholarly activity and as such constitute scholarly resources which must be clearly identifiable for the respective scientific communities and, more generally, today’s information society. In particular, packages published by standard repositories can be regarded as reliable sources which can and should be referenced (i.e. cited) by scientific works such as articles or other packages. This requires conceptual frameworks and computational infrastructure for describing bibliographic resources, general enough to encompass the needs of communities with an interest in R. These needs include support for exporting bibliographic metadata in standardized formats such as BIBTEX (Berry and Patashnik, 2010), but also facilitating bibliometric analyses and investigations of the social fabric underlying the creation of scholarly knowledge. The latter requires a richer vocabulary than commonly employed by reference management software such as BIBTEX, identifying persons and their roles in relation to bibliographic resources. For example, a thesis typically has an author and advisors. Software can have an (original) author and a translator to another language (such as from S to R). The maintainer of an R package is not necessarily an author. In this paper, we introduce the base R infrastructure (as completely available in R since version 2.14.0) for representing and manipulating such scholarly data: objects of class "person" (hereafter, person objects) hold information about persons, possibly including their roles; objects of class "bibentry" (hereafter, bibentry objects) hold bibliographic information in enhanced BIBTEX style, ideally using person objects when referring to persons (such as authors or editors). Furthermore, we indicate how this functionality is employed in the management of R packages, in particular in their ‘CITATION’ and ‘DESCRIPTION’ files. Persons and their roles Person objects can hold information about an arbitrary positive number of persons. These can be obtained by one call to person() with list arguments, or by first creating objects representing single persons and combining these via c(). Every person has at least one given name, and natural persons typically (but not necessarily, Wikipedia, 2012) have a family name. These names are specified by arguments given and family, respectively. For backward compatibility with older versions, there are also arguments first, middle and last with obvious (Western-centric) meaning; however, these are deprecated as not universally applicable: some cultures place the given after the family name, or use no family name. An optional email argument allows specifying persons’ email addresses, which may serve as unique identifiers for the persons. Whereas person names by nature may be arbitrary non-empty character strings, the state of the art in library science is to employ standardized vocabularies for person roles. R uses the “Relator and Role” codes and terms (http://www.loc.gov/marc/ relators/relaterm.html) from MARC (MAchineReadable Cataloging, Library of Congress, 2012), one of the leading collections of standards used by librarians to encode and share bibliographic information. Argument role specifies the roles using the MARC codes; if necessary, the comment argument can be used to provide (human-readable) character strings complementing the standardized role information. As an example (see Figure 1 and also ?person), consider specifying the authors of package boot (Canty and Ripley, 2012): Angelo Canty is the first author ("aut") who wrote the S original; Brian D. Ripley is the second author ("aut"), who translated the code to R ("trl"), and maintains the package ("cre"). Note that the MARC definition of the relator term “Creator” is “Use for a person or organization responsible for the intellectual or artistic content of a work.”, which maps nicely to the notion of the maintainer of an R package: the maintainer creates the package as a bibliographic resource for possible redistribution (e.g. via the CRAN package repository), and is the person (currently) responsible for The R Journal Vol. 4/1, June 2012 ISSN 2073-4859