- From: Kingsley Idehen <kidehen@openlinksw.com>
- Date: Thu, 17 Sep 2009 07:23:02 -0400
- To: Paul A Houle <devonianfarm@gmail.com>
- CC: public-lod@w3.org
Paul A Houle wrote: > I think there are a few scenarios here. > > In my mind, dbpedia.org <http://dbpedia.org> is a site for > tripleheads. I use it all the time when I'm trying to understand how > my systems interact with data from dbpedia -- for that purpose, it's > useful to see a reasonably formatted list of triples associated with > an item. A view that's isomorphic to the triples is useful for me there. > > Yes, better interfaces for browsing dbpedia/wikipedia ought to be > built -- navigation along axes of type, time, and space would be > obviously interesting, but making a usable interface for this > involves some challenges which are outside the scope of dbpedia.org > <http://dbpedia.org>; The point of linked data is anybody who wants > to make a better browsing interface for dbpedia. > > Another scenario is a site that's ~primarily~ a site for humans and > secondly a site for tripleheads and machines, for instance, > > http://carpictures.cc/ > > That particular site is built on an object-relational system which > has some (internal) RDF features. The site was created by merging > dbpedia, freebase and other information sources, so it exports > linked data that links dbpedia concepts to images with very high > precision. The primary vocabulary is SIOC, and the RDF content for a > page is ~nearly~ isomorphic to the content of the main part of the > page (excluding the sidebar.) > > However, there is content that's currently exclusive to the human > interface: for instance, the UI is highly visual: for every > automobile make and model, there are heuristics that try to pick a > "better than average" image at being both striking and representative > of the brand. This selection is materialized in the database. > There's information designed to give humans an "information scent" to > help them navigate, a concept which isn't so well-defined for > webcrawlers. Then there's the sidebar, which has several purposes, > one of them being a navigational system for humans, that just isn't > so relevant for machines. > > There really are two scenarios I see for linked data users relative > to this system at the moment: (i) a webcrawler crawls the whole > site, or (ii) I provide a service that, given a linked data URL, > returns information about what ontology2 knows about the URL. For > instance, this could be used by a system that's looking for > multimedia connected with anything in dbpedia or freebase. Perhaps I > should be offering an NT dump of the whole site, but I've got no > interest in offering a SPARQL endpoint. > > As for friendly interfaces, I'd say take a look analytically at a > page like > > http://carpictures.cc/cars/photo/car_make/21/Chevrolet > > What's going on here? This is being done on a SQL-derivative > system that has a query builder, but you could do the same thing w/ > SPARQL. We'd image that there are some predicates like > > hasCarModel > hasPhotograph > hasPreferredThumb > > starting with a URL that represents a make of car (a nameplate, > like Chevrolet) we'd then traverse the hasCarModel relationship to > enumerate the models, and then do a COUNT(*) of hasPhotograph > relationships for the cars to create a count of pictures for each > model. Generically, the construction of a page like this involves > doing "joins" and traversing the graph to show, not just the triples > that are linked to a named entity, but information that can be found > by traversing a graph. > People shouldn't be shy about introducing their own predicates; the > very nature of inference in RDF points to "creating a new predicate" > as the basic solution to most problems. In this case, > hasPreferredThumb is a perfectly good way to materialize the result of > a complex heuristic. > > (One reason I'm sour about public SPARQL endpoints is that I don't > want to damage my brand by encouraging amnesic mashups of my content; > a quality site really needs a copy of it's own data so it can make > additions, corrections, etc; one major shortcoming of Web 2.0 has > been self-serving API TOS that forbid systems from keeping a memory -- > for instance, Ebay doesn't let you make a price tracker or a system > that keeps dossiers on sellers. Del.icio.us <http://Del.icio.us> > makes it easy to put data in, but you can't get anything interesting > out. Web 3.0 has to make a clean break from this.) > > Database-backed sites traditionally do this with a mixture of > declarative SQL code and procedural code to create a view... It would > be interesting to see RDF systems where the graph traversal is > specified and transformed into a website declaritively. > Paul, A summary for the ages. This is basically an aspect of the whole Linked Data meme that is lost on too many. Thank you very much!! -- Regards, Kingsley Idehen Weblog: http://www.openlinksw.com/blog/~kidehen President & CEO OpenLink Software Web: http://www.openlinksw.com
Received on Thursday, 17 September 2009 11:23:52 UTC