On 3/23/11 10:06 AM, wenlei zhou wrote:
Thank you very much!
Today, I have read the book which is publish in
http://linkeddatabook.com/editions/1.0/#note119. In section 4.5.2, I
find several tips.
When link a dataset to other datasets, there are two different situation:
To little size dataset, the publisher can use several different type
of predictors to connect to the entities which are declared in other
datasets.
While to large size dataset, record linkage techniques can be used to
find the SameAs entities in other datasets automatically.
Regards
On 23 March 2011 21:50, Bill Roberts <[email protected]
<mailto:[email protected]>> wrote:
Although this has led to a discussion, no-one as far as I can tell
has actually tried to answer Wenlei Zhou's question.
Hope this helps:
I can create a link from my dataset to yours just by including a
triple in my dataset with one of 'your' URIs as object.
<http://mysite.com/id/1> <http://example.com/some-predicate>
<http://yoursite.com/id/ABC>
You can also declare information about links between datasets in
metadata about your dataset, using the voiD ontology - see
http://vocab.deri.ie/void
If you are thinking about the Linked Data Cloud diagram (see
http://richard.cyganiak.de/2007/10/lod/) then that is generated
every few months by Richard Cyganiak and Anja Jentzch, using some
criteria listed on that web page - the dataset must be at least
1000 triples and contain at least 50 links to other datasets
already in the diagram - and you have to make sure Richard or
Anja knows about it.
Regards
Bill
On 22 Mar 2011, at 14:58, wenlei zhou wrote:
> Hi, every one
> I'm a novice to Linked Data. In the learning of linked data, I
got several questions.
>
> 1. When public a new data set, how does it connect to other data
sets in the Linked Data Cloud. Just use the record linkage
techniques to connect two identifiers which are actually telling
the same entity? Or, is this method only applied to publishing
large new data set, not small one?
> 2. Where is the rdf data stored, which connects two data sets?
Is it just stored in a third party?
>
> Can anyone tell me the answers?
> Thank you very much!!
>
> regards,
> Zhou Wenlei
Zhou,
Example.
Given an Entity: 'Nigeria' (type: Country). Described across a number of
Linked Datasets. How would you obtain a holistic view of said Entity.
Links:
1.
http://lod.openlinksw.com/describe/?uri=http%3A%2F%2Faims.fao.org%2Faos%2Fgeopolitical.owl%23Nigeria&sas=yes
-- description of 'Nigeria' with owl:sameAs inference context enabled
2.
http://lod.openlinksw.com/fct/rdfdesc/usage.vsp?g=http%3A%2F%2Faims.fao.org%2Faos%2Fgeopolitical.owl%23Nigeria&tp=2&sas=yes
-- leveraging host DBMS metadata re. determining source Named Graphs
used in the description
3.
http://lod.openlinksw.com/fct/rdfdesc/usage.vsp?g=http%3A%2F%2Faims.fao.org%2Faos%2Fgeopolitical.owl%23Nigeria&tp=3&sas=yes
-- co-references list where clicking on each URI (while inference
context is enabled) results in the same description (a union of all
facts associated with the co-referent of all of the listed URIs)
4.
http://lod.openlinksw.com/fct/rdfdesc/usage.vsp?g=http%3A%2F%2Faims.fao.org%2Faos%2Fgeopolitical.owl%23Nigeria&tp=3
-- same as above without inference context, so clicking on each URI will
present a description scoped to that URI .
Trouble is, you can only go so far with datasets, you need a space where
the data is managed in such a way that it can deliver the solution you
seek via queries. In the example above I use the LOD Cloud Cache
instance which has 15 Billion+ triples. I could have also derived the
same answers, with some overhead of course, if I had the SPARQL query
execute a follow-your-nose style crawl across all the original source
data spaces.
This is a DBMS style problem, ultimately. The DBMS has to maintain
metadata about the data under its management. Then leverage said
metadata when answering these queries.
--
Regards,
Kingsley Idehen
President& CEO
OpenLink Software
Web: http://www.openlinksw.com
Weblog: http://www.openlinksw.com/blog/~kidehen
Twitter/Identi.ca: kidehen
