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 Stephen Paul Davis wrote:
 I understand that W3C and others have recognized that the RDF triples 
 approach in fact lacks two important parameters that will need to be 
 defined before we go much further, namely namespace and provenance. So 
 we'll  need "quintuples" instead of triples
 **
 Ivan Herman <[log in to unmask]> wrote
 Well, yes and no...

 The RDF community and, more specifically, the RDF Working Group, has to 
 come to grip with the notion of named graphs. Simply put, there should 
 be a way to consider a set of triples and identify that set with a 
 URI... Once this is somehow settled, the general framework can be used 
 to attach, eg, provenance information to a graph... So we are not 
 talking about quintuples. You can look at the named graphs as quads 
 (that is the way many system implement them) but that is only an 
 implementation detail for now.
 **

 I find this idea of "named graphs" very interesting and would like to 
 understand it better. Apologies in advance for the length of my 
 questions and comments. I hope they make some sense as my understanding 
 of linked data is rudimentary.

 At ALA Annual someone made the comment that linked data doesn't support 
 assertions in the form X said that Y is Z. Other people said this wasn't 
 true, but I didn't hear any explanations of how you could do it. I am 
 coming at this from a cataloger's perspective and for a project I am 
 working on there are times when I think I want to say things like this 
 or other things that seem to require more than three data points. I am 
 not sure how much sense this will make, but I thought I'd throw it out 
 there and see if I'm at all on the right track.

 I'd like to organize my thoughts around some issues that came up when 
 OLAC was doing our initial investigations into the potential of the FRBR 
 model to improve access to moving images (see 
 http://www.olacinc.org/drupal/?q=node/27, particularly part 3a). There 
 we were talking about works, but I'd like to work through an example 
 using language track information on DVDs.

 It's easy to see how to construct a statement that says this DVD is 
 usable in English

 DVD1 -- hasLanguage -- English

 But during our discussions, we realized that we wanted to record 
 several more specific aspects of language information, including whether 
 the language is

 Spoken, signed or written
 Within written whether it is captions (open, closed, SDH), subtitles, 
 or intertitles
 The original language or a translation
 Primary or secondary

 Primary vs. secondary might seem like an odd thing to want to know, but 
 in practice, you can go wrong if you don't make this distinction. IMDb 
 often fails on this count, which leads to a list of the most popular 
 Thai language films being topped by The Hangover Part II (2011) and 
 Rambo (2008) (see http://www.imdb.com/language/th) and The Godfather 
 (http://www.imdb.com/title/tt0068646/) is listed as if it is equally in 
 English, Italian and Latin. You also see this lack of distinction in 
 library bibliographic records, especially for educational/documentary 
 videos with a few subtitled sequences in another language.

 So maybe one way to go at this would be to combine all these 
 characteristics into one mega predicate

 DVD1 -- hasLanguagePrimaryAudio -- English

 And then map that to the less restrictive cases so

 hasLanguagePrimaryAudio -- isSubTypeOf -- hasLanguagePrimary
 hasLanguagePrimaryAudio -- isSubTypeOf -- hasLanguageAudio
 hasLanguagePrimary -- isSubTypeOf -- hasLanguage
 hasLanguageAudio -- isSubTypeOf -- hasLanguage

 so if someone is just looking at the unrefined language level they can 
 get that. But it does seem like an awful lot of possibilities to account 
 for.

 Maybe another way would be to introduce an intermediate entity between 
 the DVD and the language information like this. One advantage is that 
 you could distinguish mixed soundtracks from multiple soundtracks as in 
 statements 1 and 2 in the example below for a DVD with the movie's 
 original mixed Arabic and French soundtrack, a dubbed Spanish soundtrack 
 and an English subtitle track.

 DVD1 hasLanguageStatement LanguageStatement1
 LanguageStatement1 -- Language -- Arabic
 LanguageStatement1 -- Language -- French
 LanguageStatement1 -- LanguageLevel -- Primary
 LanguageStatement1 -- LanguageType -- Audio
 LanguageStatement1 -- LanguageOriginal -- Original
 LanguageStatement1 -- InfoSource -- Container

 DVD1 hasLanguageStatement LanguageStatement2
 LanguageStatement2 -- Language -- Spanish
 LanguageStatement2 -- LanguageLevel -- Primary
 LanguageStatement2 -- LanguageType -- Audio
 LanguageStatement2 -- LanguageOriginal -- Translation
 LanguageStatement2 -- InfoSource -- Container


 DVD1 hasLanguageStatement LanguageStatement3
 LanguageStatement3 -- Language -- English
 LanguageStatement3 -- LanguageLevel -- Primary
 LanguageStatement3 -- LanguageType -- Written
 LanguageStatement3 -- LanguageTypeWritten -- Subtitle
 LanguageStatement3 -- LanguageOriginal -- Translation
 LanguageStatement3 -- InfoSource -- Container

 And then you would have to give people who want to use this data some 
 way to connect the dots, which I'm not sure how to do.

 This approach would also be useful for ordering data. For instance, for 
 film and video, the order in which cast names are presented is 
 important, as well as the type of ordering. In addition, this could 
 allow you to make statements about where the data came from. So you 
 could have something that linked transcribed names with identifiers.

 Work1 hasCastCredits CastStatement1

 CastStatement1 hasSource Manifestation1 [or 
 http://www.imdb.com/title/tt0101531/ which is where I actually took this 
 from or some other reference source or unspecified for legacy data or 
 where someone doesn't want to bother]
 CastStatement1 hasOrder CreditsOrder

 CastStatement1 hasCredit CreditStatement1
 CreditStatement1 hasPosition 1
 CreditStatement1 hasTranscribedName "Charlie Sheen"
 CreditStatement1 hasNAR http://id.loc.gov/authorities/names/n88368094 
 [Sheen, Charlie]
 CreditStatement1 hasFunction 
 http://id.loc.gov/vocabulary/relators/act.html [actor]
 ...
 CastStatement1 hasCredit CreditStatement15
 CreditStatement1 hasPosition 15
 CreditStatement15 hasTranscribedName "Larry Fishburne"
 CreditStatement15 hasNAR http://id.loc.gov/authorities/names/no93030105 
 [Fishburne, Laurence, 1961-]
 CreditStatement1 hasFunction 
 http://id.loc.gov/vocabulary/relators/act.html [actor]

 Of course this is a lot of nesting and you'd have to make it work for 
 data consumers who didn't want all that complexity.

 How would you approach these kinds of problems with a named graph? Or 
 is this not something where you'd want a named graph? Is it better not 
 to do all this in linked data but rather some format for internal 
 consumption and just use the linked data for the simplified data that 
 external users are likely to want? Am I hopelessly on the wrong track?

 Kelley


 Kelley McGrath
 University of Oregon
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