Hi Diane,

> I think you're correct that there are a variety of reasons to 
> ensure that a "simpler, literal-based model" is possible with 
> RDA. For one thing in our years of working with data 
> providers in NSDL, we found that most newbie data providers 
> started out in the same place, with simple literals.  Some 
> were able to move up from there; some never had the interest 
> or motivation.  DCMI's experience with beginners has been similar. 

To be fair though, the NSDL scenario was taking place in a context where
DCMI itself was confused about the literal/non-literal distinction, at
least as far as its recommendation for encoding DC metadata in XML (of
which the oai_dc XML format required by OAI-PMH is essentially a
"profile", as was nsdl_dc) was/is concerned. 
 
> But I think it's pretty clear that for RDA to get the uptake 
> it needs for success we must consider the simpler model a 
> requirement.  It's not something that needs to be our primary 
> focus at this stage, but in getting the formal representation 
> of the elements "right" we need to keep the big picture in 
> the back of our minds. I firmly believe that judgment of our 
> ultimate success will rest on both those pillars.

> There will be data coming over from the legacy records that 
> cannot be converted easily (or at all) to URIs. 

Yes, but I'd just like to reiterate one of Mikael's points: the use of a
non-literal value (in the DCAM sense) does _not_ require the generation
of URIs. It _allows_ you to provide a value URI, but it doesn't
_require_ it. It's a design choice between which is the more appropriate
- based on how we model "our world" in order to enable a certain set of
functions/operations - of the two patterns

R prop "xxxxx" .

and 

R prop _:x .
_:x rdf:value "xxxxx" .

(where the blank node _:x could be replaced by a URI, but doesn't have
to be) 

And as Mikael said, either pattern can be adopted without the data
provider changing their internal database at all. It's just the
import/export routine that needs to "know" when it is mapping to a
literal (case 1, one triple) and when it is mapping to a non-literal
(case 2, two triples) 
 
Pete