Re: fundamental issues

On 2/13/15 7:43 AM, Irene Polikoff wrote:
> 1) Schema.org uses their own version/interpretation of what domain and
> range are which is different from RDFS. It is not interpreting them more
> loosely, it interprets them differently.

Actually we are saying the same thing, using different words. Loose is 
different, and I fully understand the difference, thank you.

>
> 2) I don't understand how this question relates to data validation. At
> the point when data is validated, one has to make a closed world
> assumption. What happens before and after validation, is a different
> matter. Other processes could assume open world. This does not in any
> way interfere with each other.

It relates thusly: if my data will stay in my closed world and will not, 
in that form, be used in the open world, then I can do whatever I want 
with it because no one else will ever see it. Heck, I don't even have to 
use RDF. What I do in the privacy of my own data store is my business. 
E.g. the closed world OWL mode. But if I think take that data and port 
it to the open world using those same OWL constructs, the meaning of my 
data in the open world is significantly different from the meaning in my 
closed world. Run the same operations in those two worlds and you get 
different results. The closed world OWL might result in inferences that 
you do not intend in the open world.

That's how open world and validation relate to each other: can I use the 
same instance data, unaltered, in both worlds with the same meaning? If 
not, then I need two sets of data, one for the closed world and one for 
the open world.

Not only that, there seems to be the assumption that all of the data 
that I will operate over has been designed for my closed world. The 
solutions proposed do not seem to cover the case where I aggregate data 
from the open world, data from some source that does not produce data to 
my validation specifications. That is, however, a common use case in my 
corner of the world. If that is NOT to be addressed here, I would like 
that to be explicit.

kc

>
> Irene
>
> On Fri, Feb 13, 2015 at 10:08 AM, Karen Coyle <kcoyle@kcoyle.net
> <mailto:kcoyle@kcoyle.net>> wrote:
>
>     1) schema.org <http://schema.org> does use the concepts of domains
>     and ranges, extensively, but it defines them more loosely than RDFS.
>     They are fundamental to schema.org <http://schema.org>
>
>     2) are you assuming that your data is closed-world only? If it is
>     not, are there implications to this use of rdfs:Class in the open world?
>
>     kc
>
>
>     On 2/13/15 6:35 AM, Irene Polikoff wrote:
>
>         I think we agree. They don't contribute anything to validation,
>         but if people want to use them that is OK. From the data
>         definition/data validation perspective they will be ignored.
>
>         Irene
>
>         Sent from my iPhone
>
>             On Feb 13, 2015, at 7:15 AM, Peter F. Patel-Schneider
>             <pfpschneider@gmail.com <mailto:pfpschneider@gmail.com>> wrote:
>
>             -----BEGIN PGP SIGNED MESSAGE-----
>             Hash: SHA1
>
>             I don't see that this is any reason to not let people who
>             want domain and
>             range to use domain and range.  If some people don't want
>             domain and range
>             then the solution for them is simple - they don't need to
>             use domain and range.
>
>             peter
>
>
>                 On 02/13/2015 02:18 AM, Irene Polikoff wrote:
>                 The reason to exclude domain and range is the same
>                 reason why Schema.org
>                 excluded them. They don't work in a way that is useful
>                 to a community
>                 interested in specifying what data should look like.
>
>                 In addition to not being useful, they also create
>                 problems by
>                 intersecting multiple ranges and domains, etc. They are
>                 often misused.
>
>                 So, one could call this RDFS- data. I don't think
>                 domains and ranges must
>                 be prohibited though, they could just be ignored.
>
>                 Irene
>
>                     On Feb 12, 2015, at 10:08 PM, Peter F. Patel-Schneider
>                     <pfpschneider@gmail.com
>                     <mailto:pfpschneider@gmail.com>> wrote:
>
>                 I suppose that the working group could exclude
>                 rdfs:domain and
>                 rdfs:range from the RDF graphs that it considers to be
>                 acceptable, just
>                 as OWL DL excluded certain RDF graphs.  For OWL DL that
>                 was to achieve
>                 decidability and I don't see an equivalent need here.
>
>                 peter
>
>
>                                 On 02/12/2015 04:03 PM, Holger Knublauch
>                                 wrote:
>                                 On 2/13/2015 8:19, Peter F.
>                                 Patel-Schneider wrote: Is the working
>                                 group producing a solution tailored for
>                                 RDF data, where RDF
>                                 graphs and rdf:type are important; for
>                                 RDFS data, where
>                                 rdfs:subClassOf, rdfs:subPropertyOf,
>                                 rdfs:domain, and rdfs:range
>                                 are also important; for Linked Data,
>                                 where dereferencing and
>                                 interlinking is important; or for
>                                 services data, where brevity
>                                 may be important?
>
>                                 2. Shapes and Classes
>
>                                 Are shapes RDF classes, i.e., should
>                                 shapes be the object of
>                                 rdf:tyoe triples, participate in
>                                 rdfs:subClassOf relationships,
>                                 and be the object of rdfs:domain and
>                                 rdfs:range triples?
>
>
>                             In both points you seem to assume that if we
>                             use rdfs:subClassOf
>                             then we also must use rdfs:domain and
>                             rdfs:range. Could you
>                             clarify? I would assume it is possible to
>                             use parts of the RDFS
>                             namespace without sucking in all
>                             dependencies, assuming we clarify
>                             that situation in the beginning of the
>                             specification.
>
>                             Thanks, Holger
>
>             -----BEGIN PGP SIGNATURE-----
>             Version: GnuPG v1
>
>             iQEcBAEBAgAGBQJU3ertAAoJECjN6+__QThfjz+8cH/3lpq+__zfMg09M01sCRIlDqi1
>             nslsOObD4ukEuioL/f9GQ1/__OZvcZVw6i09aNugsABbUHfTuFUIxsm__GA9+6r1ZM+t
>             kVqzewSPhH4GFp5Gcy8x4Y0pAIEBQ6__2RRYfPNClX38eFx5e/ZJ+__xfg5HSjqzpF3r
>             xVuW1+i5nge0lUJr4WF/bW/__Tj6g69TXUrXet3tNTJ1sddkxqXPo7j__BvSE1kZkBTH
>             3UsZr1yokiM6FkbxI1JJ6MIOl1BdvB__vwQaiyn38fgMjNSvTTtfvhnp3Mua8S__s4He
>             3hExQ4wUMXw0nU4ob+__71dqzvaU1o9hgRlxwgSky4gXOAmD95__U84fgpUZuVxDKWs=
>             =KorL
>             -----END PGP SIGNATURE-----
>
>
>
>
>     --
>     Karen Coyle
>     kcoyle@kcoyle.net <mailto:kcoyle@kcoyle.net> http://kcoyle.net
>     m: 1-510-435-8234 <tel:1-510-435-8234>
>     skype: kcoylenet/+1-510-984-3600 <tel:%2B1-510-984-3600>
>
>

-- 
Karen Coyle
kcoyle@kcoyle.net http://kcoyle.net
m: 1-510-435-8234
skype: kcoylenet/+1-510-984-3600

Received on Friday, 13 February 2015 16:24:44 UTC