- From: Michael Hausenblas <michael.hausenblas@deri.org>
- Date: Fri, 22 Jul 2011 11:41:47 +0100
- To: Frans Knibbe <frans.knibbe@geodan.nl>
- Cc: public-lod@w3.org
> So, does this mean that the URI of the dataset (DBPedia) is http://lod-cloud.net/dbpedia? > ? It is one URI identifying the DBpedia dataset, yes. It is likely not the authoritative one as it is not int the dbpedia.org namespace, so there may be others ... Cheers, Michael -- Dr. Michael Hausenblas, Research Fellow LiDRC - Linked Data Research Centre DERI - Digital Enterprise Research Institute NUIG - National University of Ireland, Galway Ireland, Europe Tel. +353 91 495730 http://linkeddata.deri.ie/ http://sw-app.org/about.html On 22 Jul 2011, at 11:16, Frans Knibbe wrote: > Hello Michael, > > On 2011-07-22 10:59, Michael Hausenblas wrote: >> >> Frans, >> >>> I had a quick look. But I could not find it. I had a closer look >>> now and I see the URI probably is http://dbpedia.org/void/Dataset. >>> I have tried it. Redirection to either HTML or RDF seems to be in >>> place. HTML request lead to http://dbpedia.org/void/page/Dataset, >>> which shows a table of VoID properties. The RDF redirection (to http://dbpedia.org/void/data/Dataset.rdf) >>> does not seem to work, I get an error. >> >> Sorry, you lost me here. Did you curl it or how did you get your >> findings? > > Yes, I tried curl. I have just tried it again: > > curl -H "Accept: application/rdf+xml" http://dbpedia.org/void/data/Dataset.rdf > > The response seems to be different from yesterday. Yesterday I > immediately got an error message. I am afraid I don't have the exact > message any more. The response I get now is different, a transaction > time out, which I get after waiting a bit. > > Probably this is just a temporary situation and besides the point too. >> >>> Apart from the error, somehow this is not what I expected. I >>> assumed that the dataset URI is the URI of a dataset. It is the >>> key to all other data. If you want something from a dataset, you >>> only need to know this URI. So why is the dataset URI hard to >>> find? Why isn't it used when references are made to DBpedia? Why >>> isn't it the same as the base URI (http://dbpedia.org)?. >> >> <http://lod-cloud.net/dbpedia> a void:Dataset; >> foaf:homepage <http://dbpedia.org/>; >> >> Says everything, or? > Well, let me see... > > First of all, please know that I am new to Linked Data and RDF, so > there is a chance I don't fully understand everything. > > I think what it says is that there is a thing identified by the URI http://lod-cloud.net/dbpedia > , that that thing is a dataset and that its home page is http://dbpedia.org/ > . > > So, does this mean that the URI of the dataset (DBPedia) is http://lod-cloud.net/dbpedia? > ? > > Sorry if I seem to be stupid, it is not my intention. > >> >>> Probably VoID metadata/dataset URIs will be easier to discover >>> once the /.well-known/void trick (described in paragraph 7.2 of >>> the W3C VoID document) is widely adopted. >> >> Agreed. But it's not a 'trick'. It's called a standard. > Sorry about that! > > Regards, > Frans >> >> Cheers, >> Michael >> -- >> Dr. Michael Hausenblas, Research Fellow >> LiDRC - Linked Data Research Centre >> DERI - Digital Enterprise Research Institute >> NUIG - National University of Ireland, Galway >> Ireland, Europe >> Tel. +353 91 495730 >> http://linkeddata.deri.ie/ >> http://sw-app.org/about.html >> >> On 22 Jul 2011, at 09:42, Frans Knibbe wrote: >> >>> On 2011-07-21 16:27, Michael Hausenblas wrote: >>>> >>>> >>>>> But is this really common practice nowadays? Take DBpedia for >>>>> example. What is the URI of the DBpedia dataset? Is it http://dbpedia.org? >>>>> That does not seem to resolve to a set of metadata. >>>> >>>> Did you have a look at the URI I gave you? I mean http://lod-cloud.net/void.ttl >>> I had a quick look. But I could not find it. I had a closer look >>> now and I see the URI probably is http://dbpedia.org/void/Dataset. >>> I have tried it. Redirection to either HTML or RDF seems to be in >>> place. HTML request lead to http://dbpedia.org/void/page/Dataset, >>> which shows a table of VoID properties. The RDF redirection (to http://dbpedia.org/void/data/Dataset.rdf) >>> does not seem to work, I get an error. >>> >>> Apart from the error, somehow this is not what I expected. I >>> assumed that the dataset URI is the URI of a dataset. It is the >>> key to all other data. If you want something from a dataset, you >>> only need to know this URI. So why is the dataset URI hard to >>> find? Why isn't it used when references are made to DBpedia? Why >>> isn't it the same as the base URI (http://dbpedia.org)?. >>> >>> Probably VoID metadata/dataset URIs will be easier to discover >>> once the /.well-known/void trick (described in paragraph 7.2 of >>> the W3C VoID document) is widely adopted. >>> >>>> >>>> BTW, some 30% [1] of the LOD cloud datasets are using VoID ... >>>> >>>>> Is there a general way of obtaining datasets URIs? >>>> >>>> Not to my knowledge. We're working on it in LATC [2] - Keith? >>>> >>>> Cheers, >>>> Michael >>>> >>>> [1] http://www4.wiwiss.fu-berlin.de/lodcloud/state/#data-set-level-metadata >>>> [2] http://latc-project.eu/ >>>> >>>> -- >>>> Dr. Michael Hausenblas, Research Fellow >>>> LiDRC - Linked Data Research Centre >>>> DERI - Digital Enterprise Research Institute >>>> NUIG - National University of Ireland, Galway >>>> Ireland, Europe >>>> Tel. +353 91 495730 >>>> http://linkeddata.deri.ie/ >>>> http://sw-app.org/about.html >>>> >>>> On 21 Jul 2011, at 15:19, Frans Knibbe wrote: >>>> >>>>> >>>>> Thanks for the replies. It seems that there is agreement that a >>>>> dataset should have a URI and that dereferencing that URI should >>>>> return metadata about the dataset. That is good to know. >>>>> >>>>> But is this really common practice nowadays? Take DBpedia for >>>>> example. What is the URI of the DBpedia dataset? Is it http://dbpedia.org? >>>>> That does not seem to resolve to a set of metadata. >>>>> >>>>> Is there a general way of obtaining datasets URIs? >>>>> >>>>> I can imagine an RDF dataset comprising all known dataset URIs. >>>>> And of course that dataset will have a URI itself. Does such a >>>>> dataset exist at the moment? >>>>> >>>>> Regards, >>>>> Frans >>>>> >>>>> >>>>> On 2011-07-21 12:35, Frans Knibbe wrote: >>>>>> >>>>>> Hello, >>>>>> >>>>>> I have just placed a Linked Data dataset online and now I am >>>>>> struggling with finding the best way to publish the metadata of >>>>>> the dataset. I wonder if there are best practices for >>>>>> referencing a dataset and its metadata, and for linking the two. >>>>>> >>>>>> I did find out that using the Vocabulary of Interlinked Data >>>>>> (VoID) is a good way to publish the metadata of a dataset. But >>>>>> I still need some guidance. I have come up with three questions: >>>>>> >>>>>> 1) Is it common practice/recommendable to regard a dataset a >>>>>> resource? If it is, then all datasets should have a URI, right? >>>>>> 2) If having a dataset URI is a good thing, what should be >>>>>> behind the URI? Should dereferencing the URI lead to the >>>>>> dataset metadata (a VoID file for example)? >>>>>> 3) If dereferencing a dataset URI leads to the dataset >>>>>> metadata, should there be separate HTML and RDF versions of the >>>>>> metadata? Or is it better to have a HTML page with embedded >>>>>> (RDFa) RDF data? >>>>>> >>>>>> Thanks in advance for your help, >>>>>> Frans >>>>> >>>> >>>> >>> >>> >> >> > > >
Received on Friday, 22 July 2011 10:42:32 UTC