Re: Top three levels of Dewey Decimal Classification published as linked data
Ed, Michael Hi Michael, This is really exciting news, especially for those of us Linked Data enthusiasts in the world of libraries and archives. Congratulations! +1 I haven't fully read the wiki page yet, so I apologize if this question is already answered there. I was wondering why you chose to mint multiple URIs for the same concept in different languages. I had exactly the same question, you stole it ... ... I kind of expected the assertions to hang off of a language and version agnostic URI, with perhaps dct:hasVersion links to previous versions. Indeed. http://dewey.info/class/641/ cc:attributionName OCLC Online Computer Library Center, Inc. ; cc:attributionURL http://www.oclc.org/dewey/ ; cc:morePermissions http://www.oclc.org/dewey/about/licensing/ ; dct:hasVersion http://dewey.info/class/641/2009/08/ ; dct:language de^^dct:RFC4646 ; a skos:Concept ; xhtml:license http://creativecommons.org/licenses/by-nc-nd/3.0/ ; skos:broader http://dewey.info/class/64/2003/08/about.de ; skos:inScheme http://dewey.info/scheme/2003/08/about.de ; skos:notation 641^^http://dewey.info/schema-terms/Notation ; skos:prefLabel Food drink@en, Essen und Trinken@de . Maybe rather : skos:broader http://dewey.info/class/64/2003/ ; skos:inScheme http://dewey.info/scheme/2003/08/ ; Although I don't understand why some classes have a year information in the URI (2003) and some have none? Bernard -- *Bernard Vatant *Senior Consultant Vocabulary Data Engineering Tel: +33 (0) 971 488 459 Mail: bernard.vat...@mondeca.com mailto:bernard.vat...@mondeca.com *Mondeca** *3, cité Nollez 75018 Paris France Web:www.mondeca.com http://www.mondeca.com Blog:Leçons de Choses http://mondeca.wordpress.com/ **
Re: Top three levels of Dewey Decimal Classification published as linked data
On Thu, Aug 20, 2009 at 3:53 AM, Bernard Vatantbernard.vat...@mondeca.com wrote: http://dewey.info/class/641/ cc:attributionName OCLC Online Computer Library Center, Inc. ; cc:attributionURL http://www.oclc.org/dewey/ ; cc:morePermissions http://www.oclc.org/dewey/about/licensing/ ; dct:hasVersion http://dewey.info/class/641/2009/08/ ; dct:language de^^dct:RFC4646 ; a skos:Concept ; xhtml:license http://creativecommons.org/licenses/by-nc-nd/3.0/ ; skos:broader http://dewey.info/class/64/2003/08/about.de ; skos:inScheme http://dewey.info/scheme/2003/08/about.de ; skos:notation 641^^http://dewey.info/schema-terms/Notation ; skos:prefLabel Food drink@en, Essen und Trinken@de . Maybe rather : skos:broader http://dewey.info/class/64/2003/ ; skos:inScheme http://dewey.info/scheme/2003/08/ ; Yes, thanks Bernard. In my haste I forgot to remove the language specific-ness from the skos:broader assertions in my email to Michael. I might actually recommend that the version information is removed from the object in the broader relation too: http://dewey.info/class/641/ skos:broader http://dewey.info/class/64/2003/ . As it stands now a document URI is being used in the object position, instead of the URI for the concept. uqbar:~ ed$ curl -I http://dewey.info/class/64/2003/08/about.de HTTP/1.1 200 OK Date: Thu, 20 Aug 2009 09:27:32 GMT Server: Apache/2.2.11 (Unix) PHP/5.2.10 X-Powered-By: PHP/5.2.10 Content-Location: http://dewey.info/class/64/2003/08/about.de.rdf Vary: Accept Content-Length: 2115 Content-Type: application/rdf+xml //Ed
Re: Top three levels of Dewey Decimal Classification published as linked data
On Wed, 2009-08-19 at 14:27 -0400, Panzer,Michael wrote: I would like to announce the availability of the DDC Summaries as a linked data service that uses SKOS and other vocabularies for representation [1]. Please take a look if you like. Comments, suggestions, and advice are really appreciated! Hurrah! I was looking for linked data URIs for the Dewey Decimal Classification a few months ago, and while I eventually found info:ddc/22/eng//641, these aren't very linked data as they're not dereferencable via HTTP. So I set up my own, in the format: http://purl.org/NET/decimalised#c470 The data is available in RDF/XML and N-Triples with a subset in XHTML +RDFa, all content negotiated. I've called my data the Decimalised Database of Concepts to reflect the fact that the information shouldn't be treated as necessarily exactly the same as official Dewey Decimal Classification concepts. It includes SKOS relatedMatch mappings to DBpedia and closeMatch mappings to LCSH and LCCO in many cases. In light of your announcement yesterday, I've added exactMatch mappings to dewey.info's URIs too. I don't know if this information or the mappings are any use to you. It's available under CC-BY-SA, which is not especially compatible with the CC-BY-NC-ND license used by dewey.info, but given that the vast majority of my data comes from Wikipedia, I don't really have the choice of publishing it under a different license. -- Toby A Inkster mailto:m...@tobyinkster.co.uk http://tobyinkster.co.uk
Re: Top three levels of Dewey Decimal Classification published as linked data
On Wed, Aug 19, 2009 at 7:27 PM, Panzer,Michaelpanz...@oclc.org wrote: Hi all, I would like to announce the availability of the DDC Summaries as a linked data service that uses SKOS and other vocabularies for representation [1]. Please take a look if you like. Comments, suggestions, and advice are really appreciated! Very pleased to see this happen at OCLC and I hope there's more to come! Ian
Re: data.gov now live with RDFa
Rick,
Toby already pointed out the issue with the dc: namespace.
There's also this section:
div class=hometext about=data.gov program
property=dc:description
The purpose of Data.gov is to increase public access ...
/div
The value of the @about attribute has to be a URI, and data.gov
program is not a URI. Fixing it is easy, but depends on what exactly
you want the data to say.
1. Maybe you want the text to be a description of the web page http://www.data.gov/
. Similar to the dc:title, dc:creator and dc:publisher triples that
are already present. In that case, you would want to use about=,
which is a shortcut for about=http://www.data.gov/; because an empty
URI will be treated as a relative URI, and therefore expands to the
URI of the current document. But since about= is the default anyway,
you could just drop the attribute completely and still get the same
triple.
2. Maybe you want to text to be a description of the data.gov
program, the government activity/entity, and not just a description
of the particular web page. In that case, you would need to decide on
a URI that you want to use for this entity. One easy option would be
about=#program, which again is a relative URI and would expand to http://www.data.gov/#program
. In that case, it would be nice to add some more triples about the
program.
The first option might be a bit more straightforward.
Best,
Richard
On 19 Aug 2009, at 11:50, rick wrote:
Hello All:
Just to give you a heads up the data.gov home page is now live with
RDFa tags.
http://www.data.gov/
The page has two triples. One about the page, one about the program.
We used this very simplistic approach to overcome any operational
barriers and develop experience in publishing RDFa tags.
See below for source code that parses the triples. I used the INRIA
GRDDL transform.
Have fun and I'll watch this list for feedback and such.
--
Rick
cell: 703-201-9129
web: http://www.rickmurphy.org
blog: http://phaneron.rickmurphy.org
more RDFaConsumer.java
/**
* @(#)RDFaConsumer.java
* @author r...@rickmurphy.org
*/
package gov.data;
/**
*/
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.FactoryConfigurationError;
import javax.xml.parsers.ParserConfigurationException;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import java.text.ParseException;
import java.io.UnsupportedEncodingException;
import java.io.IOException;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Element;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import java.net.URL;
public class RDFaConsumer{
private static String namespace;
/**
*/
public RDFaConsumer(String uri){
try {
DocumentBuilderFactory factory =
DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document input = builder.parse(new URL(uri).toString());
input.normalize();
DOMSource source = new DOMSource(input);
StreamResult result = new StreamResult(System.out);
StreamSource stylesheet = new StreamSource(new
URL(http://ns.inria.fr/grddl/
rdfa/2008/09/03/RDFa2RDFXML.xsl).toString());
// Use a Transformer for output
TransformerFactory tFactory = TransformerFactory.newInstance();
Transformer transformer = tFactory.newTransformer(stylesheet);
transformer.transform(source, result);
// transform the dom into RDF/XML
traverse(input);
} catch (SAXParseException spe) {
System.out.println(sax parse ex: + spe);
} catch (SAXException sxe) {
System.out.println(sax ex: + sxe);
} catch (ParserConfigurationException pce) {
System.out.println(parser config ex: + pce);
}catch (UnsupportedEncodingException ude) {
System.out.println(unsupported encoding ex: + ude);
} catch (IOException ioe) {
System.out.println(io ex: + ioe);
} catch (TransformerConfigurationException tc) {
System.out.println(transformer config ex: + tc);
} catch (TransformerException te) {
System.out.println(trasnformer ex: + te);
}
}//RDFaConsumer
/**
*/
public static void main(String[] args){
new RDFaConsumer(args[0]);
}//main
/**
*/
public void traverse(Node node){
// is there anything to do?
if (node == null) {
return;
}
int type = node.getNodeType();
Re: [Dbpedia-discussion] Dbpedia-Freebase raw dump of conditional probabilities
Tim (and anyone else who is interested) I put the raw dump of conditional probabilities on an external website (http://domino.research.ibm.com/comm/research_projects.nsf/ pages/iaa.index.html). Go the section on LinkedOpenData and Extraction of Vocabularies on this page and click on the link to the datafile. Kavitha On Aug 10, 2009, at 4:42 PM, Tim Finin wrote: Kavitha Srinivas wrote: I understand what you are saying -- but some of this reflects the way types are associated with freebase instances. The types are more like 'tags' in the sense that there is no hierarchy, but each instance is annotated with multiple types. So an artist would in fact be annotated with person reliably (and probably less consistently with /music/artist). Similar issues with Uyhurs, murdered children etc. The issue is differences in modeling granularity as well. Perhaps a better thing to look at are types where the YAGO types map to Wordnet (this is usually at a coarser level of granularity). One way to approach this problem is to use a framework to mix logical constraints with probabilistic ones. My colleague Yun Peng has been exploring integrating data backed by OWL ontologies with Bayesian information, with applications for ontology mapping. See [1] for recent papers on this as well as a recent PhD thesis [2] that I think also may be relevant. [1] http://ebiquity.umbc.edu/papers/select/search/html/ 613a353a7b693a303b643a37383b693a313b643a303b693a323b733a303a3b693a 333b733a303a3b693a343b643a303b7d/ [2] http://ebiquity.umbc.edu/paper/html/id/427/Constraint- Generation-and-Reasoning-in-OWL
RE: Top three levels of Dewey Decimal Classification published as linked data
Hi Ed I haven't fully read the wiki page yet, so I apologize if this question is already answered there. I was wondering why you chose to mint multiple URIs for the same concept in different languages. [...] I kind of expected the assertions to hang off of a language and version agnostic URI, with perhaps dct:hasVersion links to previous versions. http://dewey.info/class/641/ cc:attributionName OCLC Online Computer Library Center, Inc. ; cc:attributionURL http://www.oclc.org/dewey/ ; cc:morePermissions http://www.oclc.org/dewey/about/licensing/ ; dct:hasVersion http://dewey.info/class/641/2009/08/ ; dct:language de^^dct:RFC4646 ; a skos:Concept ; xhtml:license http://creativecommons.org/licenses/by-nc-nd/3.0/ ; skos:broader http://dewey.info/class/64/2003/08/about.de ; skos:inScheme http://dewey.info/scheme/2003/08/about.de ; skos:notation 641^^http://dewey.info/schema-terms/Notation ; skos:prefLabel Food drink@en, Essen und Trinken@de . A very good question (and not an easy one to answer). The short answer would be: Language _is_ an element of the domain to be described (Dewey concepts), so a different language should generate a different URI, because it describes a separate instance of a concept. A longer answer: My basic premise here was that a URI like http://dewey.info/class/641/ should indentify class 641 across all versions/languages of the DDC, not just the most current version or a multilingual version. Why? 1. Labels can change over time for a given class, which could lead to inconsistencies with the SKOS model. For example, at one point in time class 210 had the prefLabel Natural theology; now it has the prefLabel Philosophy theory of religion (which reflects changes to its semantics as well). This would lead to problems when hanging them from one concept: http://dewey.info/class/641/ skos:prefLabel Natural theology@en; skos:prefLabel Philosophy theory of religion@en; ... skos:prefLabel Religionsphilosophie, Religionstheorie@de. 2. The prefLabel is not the only relationship that might be dependent on the concept language. And many of these relationships are not used with plain literals in object position that can be disambiguated with a language tag. Semantic relationships may be different for a concept in the German version of the DDC. Example: 220.5312 Luther-Bibel und Revisionen is a concept that, because of an expansion, only exists in the German edition. There has to be a way to identify this class as a German edtion concept, not only as a Dewey concept that happens to only have a German caption. 3. One could argue that this would not be a relevant counter-argument if translations where 100% interoperable (i.e., 220.5312 might one day be included in the English edition as Luther Bible and revisions. (Interoperability in this case would mean that no other translation or the English edition could have claimed this number to coin a different concept.) But translations are not always perfectly synchronized. So http://dewey.info/class/641/2008/01/03/ in Portugese could in fact be a translation of an earlier version of the English concept, e.g. http://dewey.info/class/641/2005/08/09/about.en (that might have been updated with different index terms, different semantic relationships and so on in the meantime). 4. Finally, having different identifiers for the same concept in a different language, or, more precisely, for a concept with the same Dewey number, makes it possible to answer very useful questions like: Which concepts exist in the German but not in the English edition? --- The compromise here is to use language as part of the document URIs (as a dimension of the representation), not as part of the abstract URIs. So, if you want to refer to a class, or timestamped version, you can do so in an abstract way: http://dewey.info/class/641/ - 303 See Other: http://dewey.info/class/641/about http://dewey.info/class/641/2003/ - 303 See Other: http://dewey.info/class/641/2003/about A 303 points a user agent to the generic document which is /about. Whereas when you want to refer to a specific language or format, you have to use a specific URI for an information resource, e.g., http://dewey.info/class/641/about.de or http://dewey.info/class/641/2003/about.de. So language _is_ recognized as part of the domain, but only as part of representations, not of concepts. See how multiple skos:prefLabel assertions can be made using the same subject? To illustrate why I think this is important consider how someone may use the resources at dewey.info: http://openlibrary.org/b/OL11604988M dct:subject http://dewey.info/class/641/ . If we follow our nose to http://dewey.info/class/641 we will get back some RDF, but the description we get isn't about the subject http://dewey.info/class/641/ so what are we to make of the above assertion? Going back the the premise, I
Re: [Dbpedia-discussion] Dbpedia-Freebase raw dump of conditional probabilities
On Thu, Aug 20, 2009 at 12:57 PM, Kavitha Srinivasksrin...@gmail.com wrote: I put the raw dump of conditional probabilities on an external website (http://domino.research.ibm.com/comm/research_projects.nsf/ pages/iaa.index.html). Go the section on LinkedOpenData and Extraction of Vocabularies on this page and click on the link to the datafile. It strikes me that this is the kind of thing it would be useful for publish as Linked Data. In other words, rather than analyzing instances, calculating a bunch of conditional probabilities, and then publishing a bunch of [ sameAs | equivalentClass | seeAlso | whatever ] assertions, one could publish a bunch of conditional probabilities or other similarity values, with some indication of the type of similarity measure used and links to the specific instance sets used to calculate the values. Others could then use these measures as they wished, setting their own thresholds for when to consider something an equivalence relation or not. Are there any vocabularies that might be used to publish such as data set as Linked Data?
Re: Top three levels of Dewey Decimal Classification published as linked data
On Thu, Aug 20, 2009 at 1:50 PM, Panzer,Michaelpanz...@oclc.org wrote: Whereas when you want to refer to a specific language or format, you have to use a specific URI for an information resource, e.g., http://dewey.info/class/641/about.de or http://dewey.info/class/641/2003/about.de. So language _is_ recognized as part of the domain, but only as part of representations, not of concepts. I don't understand this part. I understand why you ought to have language-specific (and versioned) concepts for the DDC. But then it seems to me that you should have language-specific (and versioned) URIs for the *concepts*, not just for the information resources that represent them. As it stands (and as Ed pointed out), you seem to be asserting that your information resources are SKOS Concepts. (For what it's worth, I agree with Pat Hayes that one ought to be able to have a single URI that provides access to the information resource and at the same time refers to the abstract concept. But that's not how everyone else is doing it.)
Re: [Dbpedia-discussion] Dbpedia-Freebase raw dump of conditional probabilities
Hi Ryan, Ryan Shaw wrote: On Thu, Aug 20, 2009 at 12:57 PM, Kavitha Srinivasksrin...@gmail.com wrote: I put the raw dump of conditional probabilities on an external website (http://domino.research.ibm.com/comm/research_projects.nsf/ pages/iaa.index.html). Go the section on LinkedOpenData and Extraction of Vocabularies on this page and click on the link to the datafile. It strikes me that this is the kind of thing it would be useful for publish as Linked Data. In other words, rather than analyzing instances, calculating a bunch of conditional probabilities, and then publishing a bunch of [ sameAs | equivalentClass | seeAlso | whatever ] assertions, one could publish a bunch of conditional probabilities or other similarity values, with some indication of the type of similarity measure used and links to the specific instance sets used to calculate the values. Others could then use these measures as they wished, setting their own thresholds for when to consider something an equivalence relation or not. Are there any vocabularies that might be used to publish such as data set as Linked Data? UMBEL has a specific vocabulary and set of properties for this. See the umbel:withAlignment and umbel:withLikelihood properties: http://www.umbel.org/technical_documentation.html#vocabulary Thanks, Mike
