Explanation for binary files inside source package according to
  https://lists.debian.org/debian-devel/2013/09/msg00332.html

Files: data/bgt-data.rda
Documented: man/bgt-data.Rd
  BGT-data Sample Data Set

Files: data/ch-data.rda
Documented: man/ch-data.Rd
  CH-data Sample Data Set

Files: R/sysdata.rda
Documentation: dump of system data of R run.

 -- Andreas Tille <tille@debian.org>  Tue, 19 Mar 2019 22:25:59 +0100
