Agree with Lori. If you have tabulated data, csv is better than rda
because it's plain text and can easily be imported by many software, not
just R. People can also use an editor or command line tool like grep or
head to inspect the file. OTOH rda/rds files are R specific so can only
be used
Personally: I think it depends on the use case and the type of data being
provided as well as the size. Raw data is probably more adaptable for various
usage even extending beyond expected use however it can be large; processed
data can be saved compressed and greatly reduce package/data
