Re: [foaf-dev] sameAs was Re: Linking foaf and other rdf documents/resources

On 4 July 2011 19:18, Bruce Whealton <bruce-IKflticWDqMk+I/[email protected]> wrote:
> Mischa,
> Thanks, that is a good point.  If I wanted to use owl: sameAs, I should use
> the identifier that refers to the people that are the same not the
> documents.  As soon as you said it, I was thinking it was obvious and I
> should have realized that previously.
>
> Speaking of that video series...  do you know a good way to create a sitemap
> of a collection of RDF files?  Maybe any sitemap generation tool would treat
> xml and rdf files the same. I’m not sure though about that.

Semantic sitemap?

http://notes.3kbo.com/semantic-sitemap

> Bruce
>
> From: Mischa Tuffield
> Sent: Sunday, July 03, 2011 7:03 PM
> To: Bruce Whealton
> Cc: foaf-dev-RyYwo1q5J+qsOXdr9/[email protected]
> Subject: Re: Owl:sameAs was Re: [foaf-dev] Linking foaf and other rdf
> documents/resources
>
> Hi,
>
> <snip/>
>
> On 3 Jul 2011, at 22:05, Bruce Whealton wrote:
>
> I found a great video on Linked Data that is very helpful, especially in
> describing many of these issues, though your explanation had made things
> clear too. <wlEmoticon-smile[1].png>
>
>
> Great news !
>
> The video presentation is here:
> http://videolectures.net/iswc08_heath_hpldw/
> and they mention the 303 redirects too.  They didn’t get into the specifics
> of that, though.  I’ll have to learn how to implement this – any tips are
> welcome.
>
>
> I haven't watched that but am sure Tom et al are talking sense.
>
> I realized that the #me isn’t really the same as it’s html equivalent.  When
> you use http://brucewhealton.us/BruceWhealtonJr/foaf.rdf#me the #me just
> gets stripped off.
> I did want to see if I could get clarification using owl:sameAs.  I guess
> you had already mentioned that it doesn’t matter if I use foaf:Person as the
> container tag or foaf: Description to contain all my information.  I can
> still distinguish between how to refer to and identify myself as different
> from a document about myself.  So, would I use owl:sameAs inside my foaf
> file, about me, to link to other documents about me?  I guess it would be
> wrong to say http://brucewhealton.us/BruceWhealtonJr/foaf.rdf#me owl:sameAs
> http://path/to/anotherdocumentaboutme/ because the subject of that triple is
> referring to me, not the document about me.  But if I leave off the #me then
> I can say that one foaf document about me is the same as another document
> about me... both are about the same person.  Is that right?
>
>
> Yes I guess that all makes perfect sense.
>
> I would be happy to say that two foaf:Person URIs are owl:sameAs :
>
> <http://mmt.me.uk/foaf.rdf#mischa> owl:sameAs
> <http://example.com/service/mischat#me> .
>
> But I wouldn't model two foaf:Documents as being same as, I would use
> rdfs:seeAlso.
>
> <http://mmt.me.uk/foaf.rdf> rdfs:seeAlso <http://example.com/service/mischa>
> .
>
> as in if you are interested in the triples in this documents have a look at
> this other document.
>
> Can I say that my foaf profile document is owl:sameAs my doac document about
> me – doac is Description of a Career, a vocabulary used for describing one’s
> resume of skills, work experience and education.  And for the purposes of
> Genealogy I might have a bio.rdf file as well, that uses the bio vocabulary
> and maybe relationships biography, both extended from FOAF.  I guess they
> are all documents I can relate using owl:sameAs
>
>
> You could do that, but I wouldn't suggest doing it. Conceptually sameAs'ing
> two foaf:Person URIs makes sense, two identifiers for the same person. But
> sameAs'ing two documents and asserting that they are the same thing doesn't
> make that much sense to me. I would consider using rdfs:seeAlso between the
> two foaf:Documents and relying of the foaf:Person's found in each document
> to share common identifiers.
>
> Mischa
>
> Thanks,
> Bruce
>
> ++++++++++++++++++++++++++++++++++++++++++++++++++
> Bruce Whealton, Owner Future Wave Designs
> FOAF: http://whealton.info/BruceWhealtonJr/foaf.rdf
> Vcard: http://whealton.info/BruceWhealtonJr/brucewhealtonvcard.html
> Web Design and Development http://FutureWaveDesigns.com
> http://futurewavedesigns.com/wordpress/
> Web Technology wiki: http://futurewavedesigns.com/w/
> ++++++++++++++++++++++++++++++++++++++++++++++++++
>
> Hi Bruce,
>
> <snip/>
>
> On 29 Jun 2011, at 16:47, Bruce Whealton wrote:
>
> Mischa, (and others)
>                This is very helpful.  So, I was looking at your profile or
> should we call it FOAF file – I’m trying to get the wording right, if there
> is a right way to say these things.
>
>
> Both are fine. http://mmt.me.uk/foaf.rdf is my "FOAF file", my "FOAF profile
> document", or simply a document with some FOAF data in it ... again, you
> seem to be saying the right things™ :)
>
>
> I’m not sure I have a good handle on the use of #me or #danbri.  I thought I
> understood it but my understanding would suggest that one would always have
> to use that when referring to the person you foaf:know.
>
>
>
> No not at all. the #me or #danbri this, is just a convention for using hash
> URIs for picking a foaf:Person URI. They are not all hash URIs, have a look
> at Tom Heath's FOAF profile, he uses 303-redirection and has a non-hash URI
> for the foaf:Person which represents him.
>
>
> So, in an html document, #danbri or #mischa is a named anchor and a link to
> a domain and path suffixed with #mischa would take one to that named anchor
> in the document.  So, what does this mean in RDF files?
>
>
> It is just another URI within an RDF document. This is so the document
> describing me http://mmt.me.uk/foaf.rdf can have a different URI from the
> URI that describes me http://mmt.me.uk/foaf.rdf#mischa . That is
> http://mmt.me.uk/foaf.rdf is NOT the same as
> http://mmt.me.uk/foaf.rdf#mischa these are different unique identifiers.
>
> When would you use #me versus #mischa?  I thought maybe it meant that in a
> document about oneself, you would use #me to refer to yourself as opposed to
> someone else in that document.
>
>
> You can use anything you like. The convention is to use the following
> triples:
>
> <http://mmt.me.uk/foaf.rdf> a foaf:PersonalProfileDocument .
> <http://mmt.me.uk/foaf.rdf> foaf:primaryTopic
> <http://mmt.me.uk/foaf.rdf#mischa> .
> <http://mmt.me.uk/foaf.rdf#mischa> a foaf:Person .
>
> The above triples ^^ state. <http://mmt.me.uk/foaf.rdf> is a FOAF document.
> The FOAF document has a primaryTopic which is
> <http://mmt.me.uk/foaf.rdf#mischa>, and URI
> <http://mmt.me.uk/foaf.rdf#mischa> is of type foaf:Person.
>
>
> Next question: you said: Usually it would be a foaf:Person URI and not a
> foaf:Document URI, as in, "Mischa knows Danbri" not "Mischa knows a Document
> on the web which talks about Danbri".
>
>
> so
>
> <http://mmt.me.uk/foaf.rdf#mischa> foaf:knows <http://danbri.org/foaf.rdf> .
> (is semantically incorrectly)
>
> and
>
> <http://mmt.me.uk/foaf.rdf#mischa> foaf:knows
> <http://danbri.org/foaf.rdf#danbri> .
>
> Like you said above, you are spot on.
>
> So, does that mean you want to refer to the foaf:Person container tag inside
> the document and not the foaf: Description container?  Or would you have one
> document that serves as a foaf:Person URI and another that serves as a
> foaf:Description URI?
>
>
> Either or. The former is what I do and Tom Heath does the later
> http://tomheath.com/home/rdf both are fine. I personally think the former is
> easier but that is a matter of personal preference.
>
>  and you were saying that it would be incorrect to say you foaf:knows the
> resource located by the following:
> <rdf:Description
> rdf:about="http://www.okkam.org/ens/id9efc2692-8bf0-4546-8eee-42877fa60ac6">
> This doesn’t actually represent a foaf:Person does it?  It is a document
> about the person.
>
>
> It looks like an HTML document to me, but I haven't bothered looking that,
> but naively it looks like URI for a person.
>
> http://sig.ma/search?q=http://www.okkam.org/ens/id9efc2692-8bf0-4546-8eee-42877fa60ac6
>
>
> You then write that this is more useful with the email address because there
> can be more than one person in a foaf file.
> <#foo> foaf:knows _:bnode0 .
> _:bnode0 a foaf:Person .
> _:bnode0 rdfs:seeAlso <http://foozle.example/foaf.rdf> .
> _:bnode0 foaf:name "Joe Bloggs" .
> _:bnode0 foaf:mbox <mailto:joe.bloggs-tvT2FxLsLtVKTLD/[email protected]> .
>
> Can you also use a nodeID to refer to Joe Bloggs in that document?  This is
> related to my above question about the meaning of using #me or #mischa.
>
>
> Of course you can :)
>
>
> Next question: Since we cannot mix different RDF serialization formats in
> the same file, how would you represent using RDF/XML the above statements
> where you are using blank nodes?  Often times I am reading about using a
> vocabulary
>
>
> Have a look a tool for converting turtle to rdf/xml if that is what you
> want. See libraptor or similar.
>
> and I run across examples like the above and I’m thinking, but my document
> is in an XML format and this is just showing it in Tuttle with blank nodes.
> Can you use blank nodes in RDF/XML?
>
>
> Yes, your example RDF/XML:
>
>
>
> I had been using
> <foaf:knows>
>         <foaf:Person>
> ...
>          <rdfs:seeAlso rdf:resource=”http://url/pathto/foaf.rdf"/>
>         </foaf:Person>
> </foaf:knows>
>
>
> has a blank node it in, worth playing with software which parses back and
> forward from RDF/XML -> Turtle. That might help you figure out what it going
> on ...
>
>
>
> Thanks,
> Bruce
>
>
> Your welcome,
>
> Mischa
>
>
>
> From: Mischa Tuffield
> Sent: Wednesday, June 29, 2011 3:55 AM
> To: Bruce Whealton
> Cc: foaf-dev-RyYwo1q5J+qsOXdr9/[email protected]
> Subject: Re: [foaf-dev] Linking foaf and other rdf documents/resources
>
> Hello
>
> comments inline:
>
> On 29 Jun 2011, at 01:11, Bruce Whealton wrote:
>
> Hello all,
>                 So, there are a few ways that one can link various profiles,
> or RDF FOAF files/resources.  I’m wondering if there is a best practice.
>
>
> Not sure if there is any best practice, I would say that foaf:knows'ing a
> foaf:Person URI is the "best way" as it slightly less costly to query, but
> will comment further below:
>
> FWIW, I think I make use of all three of the methods you list below in my
> foaf file http://mmt.me.uk/foaf.rdf
>
> I had been using
> <foaf:knows>
>         <foaf:Person>
> ...
>          <rdfs:seeAlso rdf:resource=”http://url/pathto/foaf.rdf"/>
>         </foaf:Person>
> </foaf:knows>
>
>
> In the above method if your rdf looks like :
>
> <#foo> foaf:knows _:bnode0 .
> _:bnode0 a foaf:Person .
> _:bnode0 rdfs:seeAlso <http://foozle.example/foaf.rdf> .
>
> You will need to give the foaf:Person ( _:bnode0) an inverse functional
> property, something like "foaf:homepage or foaf:weblog or foaf:mbox_sha1sum"
> as the above fragment does give the foaf:Person any unique identifiers.
>
> i.e.
>
> <#foo> foaf:knows _:bnode0 .
> _:bnode0 a foaf:Person .
> _:bnode0 rdfs:seeAlso <http://foozle.example/foaf.rdf> .
> _:bnode0 foaf:name "Joe Bloggs" .
>
> In english I make that to be. "I know this person, if you look here [1] you
> can find information about this person, and his name (ambiguously - as in
> there could be two people called joe bloggs in the document I point to) is
> Joe Bloggs"
>
> [1] <http://foozle.example/foaf.rdf>
>
>
> ^^ is not as useful as :
>
> <#foo> foaf:knows _:bnode0 .
> _:bnode0 a foaf:Person .
> _:bnode0 rdfs:seeAlso <http://foozle.example/foaf.rdf> .
> _:bnode0 foaf:name "Joe Bloggs" .
> _:bnode0 foaf:mbox <mailto:joe.bloggs-tvT2FxLsLtVKTLD/[email protected]> .
>
> In english I make that to be. "I know this person, if you look here [1] you
> can find information about this person, and his name (ambiguously) is Joe
> Bloggs, but he is the person which is on the end of this [2] email address .
>
> [1] <http://foozle.example/foaf.rdf>
> [2] <mailto:joe.bloggs-tvT2FxLsLtVKTLD/[email protected]>
>
>
> But some FOAF profiles I’ve seen setup with method #2.
> <rdf: Description rdf:
> about=”http://pathToFileAboutPerson/longstringofcharacters” >
>       ... information about the person
> </rdf: Description>
>
> then further down there would be a
> <foaf: knows
> resource=”http://pathToFileAboutPerson/longstringofcharacters”/>
>
>
> So, in this example "http://pathToFileAboutPerson/longstringofcharacters" is
> or should be a foaf:Person URI. I noticed that some people were doing this
> wrong, and were foaf:knows'ing a foaf:Document URI which is not correct in
> my books.
>
>
> I assume that the
> about="http://pathToFileAboutPerson/longstringofcharacters” refers to a FOAF
> file but I guess it doesn’t have to link to a foaf file.
>
>
> Usually it would be a foaf:Person URI and not a foaf:Document URI, as in,
> "Mischa knows Danbri" not "Mischa knows a Document on the web which talks
> about Danbri".
>
> I wonder if there is a benefit to using method #2 or a best practice that
> favors this?  I can see that it might make it easier if one had to refer,
> more than once, to the resource that represents a person (through their FOAF
> profile) in a document.
>
>
> As above, method 2 is easier to process.
>
> As one uses more vocabularies and has more extensive rdf files, it becomes
> more likely that one is going to make numerous assertions about that person
> (resource).
> Most importantly though, will there be any difference in the ability of
> crawlers or other apps to follow the links between various FOAF profile
> files?
>
>
> Regarding crawling, both of the above methods should work, especially given
> that in your bnode example at the start, you rdfs:seeAlso the foaf Document.
>
> Mischa
>
> Thanks,
> Bruce
> ++++++++++++++++++++++++++++++++++++++++++++++++++
> Bruce Whealton, Owner Future Wave Designs
> FOAF: http://whealton.info/BruceWhealton1/foaf.rdf
> Vcard: http://whealton.info/BruceWhealton1/brucewhealtonvcard.html
> Web Design and Development http://FutureWaveDesigns.com
> http://futurewavedesigns.com/wordpress/
> Web Technology wiki: http://futurewavedesigns.com/w/
> ++++++++++++++++++++++++++++++++++++++++++++++++++
> _______________________________________________
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> foaf-dev-RyYwo1q5J+qsOXdr9/[email protected]
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>
>
> ___________________________________
> Mischa Tuffield PhD
> Email: [email protected]
> Homepage - http://mmt.me.uk/
> +44(0)208 439 8200  http://www.garlik.com/
> Registered in England and Wales 535 7233 VAT # 849 0517 11
> Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD
>
>
>
> ___________________________________
> Mischa Tuffield PhD
> Email: [email protected]
> Homepage - http://mmt.me.uk/
> +44(0)208 439 8200  http://www.garlik.com/
> Registered in England and Wales 535 7233 VAT # 849 0517 11
> Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD
>
>
>
> ___________________________________
> Mischa Tuffield PhD
> Email: [email protected]
> Homepage - http://mmt.me.uk/
> +44(0)208 439 8200  http://www.garlik.com/
> Registered in England and Wales 535 7233 VAT # 849 0517 11
> Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD
>
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