<br><br><div class="gmail_quote">On Sat, Feb 13, 2010 at 7:02 AM, Martin Hepp (UniBW) <span dir="ltr"><<a href="mailto:martin.hepp@ebusiness-unibw.org">martin.hepp@ebusiness-unibw.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Dear all:<br>
<br>
In the context of the GoodRelations ontology, there is a regular need to link<br>
<br>
1. a data entity (e.g. representing a company, a product, or an offer)<br>
<br>
with<br>
<br>
2. the URI of a XHTML/HTML Web Resource that contains human-readable information about that entity (often combining the info for multiple such entities, i.e. it is NOT a direct representation of the data entity).<br>
<br>
Example: We define Microsoft as a business entity in our own namespace and want to preserve a link to the established, browsable resource.<br>
<br>
foo:microsoft a gr:BusinessEntity;<br>
gr:legalName "Microsoft Corp.".<br>
<br>
Up to now, we generally use and recommend rdfs:seeAlso for the link from the data entity to the Web page URI, e.g.<br>
<br>
foo:microsoft a gr:BusinessEntity;<br>
gr:legalName "Microsoft Corp.";<br>
rdfs:seeAlso <<a href="http://www.microsoft.com/" target="_blank">http://www.microsoft.com/</a>>.<br>
<br>
Note that we cannot simply do content negotiation (i.e. redirect http requests for html to <a href="http://www.microsoft.com" target="_blank">http://www.microsoft.com</a>), because of practical and theoretical reasons. Also, content negotiation is IMO no substitute for a traversable link from the data node to the HTML node in the graph of data).<br>
<br>
The initial motivation for rdfs:seeAlso was that it does not require importing a second ontology like FOAF, and I would also hold that using rdfs:seeAlso is, in principle, correct.<br>
<br>
However, due to the growing amount of links on the Web of Linked Data, rdfs:seeAlso is now being used so frequently that it has become too unspecific for our purpose.<br>
If there are 20+ rdfs:seeAlso links from an entity, e.g. to images and other resources, it's hard for a user agent to spot the single one link that points to the Web page, e.g. for actually buying a product.<br>
<br>
Now, the two main candidate predicates for replacing rdfs:seeAlso are IMHO<br>
<br>
1. foaf:topic<br>
and<br>
2. foaf:page.<br>
<br>
I have seen many usages of foaf:topic in such scenarios, but from reading the FOAF spec, I think that foaf:page is much more appropriate.<br></blockquote><div><br>It's not about being more "appropriate" really since there are inverse of each other, follow the domain/range to know which one to use, see <a href="http://xmlns.com/foaf/spec/#term_page">http://xmlns.com/foaf/spec/#term_page</a><br>
</div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
Proposed Pattern:<br>
<br>
foo:microsoft a gr:BusinessEntity;<br>
gr:legalName "Microsoft Corp.";<br>
foaf:page <<a href="http://www.microsoft.com/" target="_blank">http://www.microsoft.com/</a>>.<br>
<br>
foaf:topic could be used for linking back from the Web page URI to the data entity URI, e.g.<br>
<br>
<<a href="http://www.microsoft.com/" target="_blank">http://www.microsoft.com/</a>> foaf:topic foo:microsoft.<br></blockquote><div><br>foaf:topic domain is foaf:Document, range is owl:Thing, it works.<br> <br></div>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
What's your opinion on that? Will that work with your software applications? Or should we use foaf:topic instead? If so, in which direction?<br>
<br>
Alternative 1:<br>
<br>
foo:microsoft a gr:BusinessEntity;<br>
gr:legalName "Microsoft Corp.".<br>
<br>
<<a href="http://www.microsoft.com/" target="_blank">http://www.microsoft.com/</a>> foaf:topic foo:microsoft.<br></blockquote><div><br>ok.<br> </div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
Alternative 2:<br>
<br>
foo:microsoft a gr:BusinessEntity;<br>
gr:legalName "Microsoft Corp.";<br>
foaf:topic <<a href="http://www.microsoft.com/" target="_blank">http://www.microsoft.com/</a>>.<br>
<br>
I personally think that the second alternative is wrong, because the data entity does not describe the Web page, but vice versa.<br></blockquote><div><br>Right, <<a href="http://www.microsoft.com/" target="_blank">http://www.microsoft.com/</a>> is a foaf:Document, you should not use this alternative.<br>
<br>Steph.<br> </div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
Since this decision will be important for compatibility with SemWeb / Linkedata applications, I would be very thankful for your comments.<br>
<br>
Best wishes<br>
<br>
Martin Hepp<br>
<br>
-- <br>
<br>
-- <br>
--------------------------------------------------------------<br>
martin hepp<br>
e-business & web science research group<br>
universitaet der bundeswehr muenchen<br>
<br>
e-mail: <a href="mailto:hepp@ebusiness-unibw.org" target="_blank">hepp@ebusiness-unibw.org</a><br>
phone: +49-(0)89-6004-4217<br>
fax: +49-(0)89-6004-4620<br>
www: <a href="http://www.unibw.de/ebusiness/" target="_blank">http://www.unibw.de/ebusiness/</a> (group)<br>
<a href="http://www.heppnetz.de/" target="_blank">http://www.heppnetz.de/</a> (personal)<br>
skype: mfhepp twitter: mfhepp<br>
<br>
Check out GoodRelations for E-Commerce on the Web of Linked Data!<br>
=================================================================<br>
<br>
Project page:<br>
<a href="http://purl.org/goodrelations/" target="_blank">http://purl.org/goodrelations/</a><br>
<br>
Resources for developers:<br>
<a href="http://www.ebusiness-unibw.org/wiki/GoodRelations" target="_blank">http://www.ebusiness-unibw.org/wiki/GoodRelations</a><br>
<br>
Webcasts:<br>
Overview - <a href="http://www.heppnetz.de/projects/goodrelations/webcast/" target="_blank">http://www.heppnetz.de/projects/goodrelations/webcast/</a><br>
How-to - <a href="http://vimeo.com/7583816" target="_blank">http://vimeo.com/7583816</a><br>
<br>
Recipe for Yahoo SearchMonkey:<br>
<a href="http://www.ebusiness-unibw.org/wiki/GoodRelations_and_Yahoo_SearchMonkey" target="_blank">http://www.ebusiness-unibw.org/wiki/GoodRelations_and_Yahoo_SearchMonkey</a><br>
<br>
Talk at the Semantic Technology Conference 2009: "Semantic Web-based E-Commerce: The GoodRelations Ontology"<br>
<a href="http://www.slideshare.net/mhepp/semantic-webbased-ecommerce-the-goodrelations-ontology-1535287" target="_blank">http://www.slideshare.net/mhepp/semantic-webbased-ecommerce-the-goodrelations-ontology-1535287</a><br>
<br>
Overview article on Semantic Universe:<br>
<a href="http://www.semanticuniverse.com/articles-semantic-web-based-e-commerce-webmasters-get-ready.html" target="_blank">http://www.semanticuniverse.com/articles-semantic-web-based-e-commerce-webmasters-get-ready.html</a><br>
<br>
Tutorial materials:<br>
ISWC 2009 Tutorial: The Web of Data for E-Commerce in Brief: A Hands-on Introduction to the GoodRelations Ontology, RDFa, and Yahoo! SearchMonkey <a href="http://www.ebusiness-unibw.org/wiki/Web_of_Data_for_E-Commerce_Tutorial_ISWC2009" target="_blank">http://www.ebusiness-unibw.org/wiki/Web_of_Data_for_E-Commerce_Tutorial_ISWC2009</a><br>
<br>
<br>
</blockquote></div><br>